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Every year we do a large scientific investigation for our science fair. And I thought that there might be some in the hive who would like to see how scientific inquiry works, especially while we are in the middle of it rather than all tidied up and sugar coated at the end. :001_smile:

 

We are studying Earth Science this year and have done 9 weeks each of astronomy, geology, and oceanography, so there are 9 left for our investigations. Earth Science is always the hardest science topic for kids to study IMHO because the processes are slow (plus I have never studying Earth Science (ever) so I am always at a loss.) I have a 6th grader and a 2nd grader, and the 6th grader will try for the regional science fair this year so there a lot of restrictions on originality and independence.

 

Week 1

 

6th grader:

 

We discuss what he will study and decide that since he has been reading about Oceanography most recently and has just started learning to sail that he would like to study the ocean. I try to sway him towards studying life in rock pools, maybe how different animals are affected by the tides or prevailing wind etc. He is not interested. "That's Biology; I want to study Earth Science!" sigh. "ok, so what are you interested in?" "I want to study the movement of sand." :001_huh: hummmm. Now, how is an 11-year old going to do that? After some more questioning, he tells me that he would like to see how sand moves differently depending on the location in the bay he sails in. Ok, that is a good question, just maybe not answerable without a million dollars worth of equipment.

 

We go to the library, and find a textbook on seashore ecology which has a chapter on how waves affect animals (my original idea). But not much else. Next, we hunt for articles on sand movement in the peer-reviewed science journals using the library databases. We find that scientists use radioactive sand that they can then trace or they study a shoreline over the period of 5 years. Ok, neither of those are possible. But we discuss how maybe we can use a different color sand and dump it in the water and time its movement and measure its direction. We also brainstorm all the factors that could affect sand movement: sand size, wind speed and direction, prevailing currents, orientation of the bay to the wind and currents (sheltered?), obstacles (rocks, jetties), slope of the shore. WOW. That is a lot of variables to control once we set up the experiment.

 

On Saturday, after sailing he takes a look around the bay to see if the sand moves at all. It does. That is all the information he brings back.:001_huh: Next, we go to a different beach and collect the sand there (which might be a different color), and collect magnetite (magnetic soil mixed into the sand on this beach, it is black and will definitely show up).

 

Finally, we discuss how much he can generalize given the sampling he is considering. Tomorrow, we plan to put the collected sand and magnetite in the water and see if we have any chance of measuring anything, or if this is just a wild goose chase (which it definitely could be).

 

Time: 4 hours including discussions

 

2nd grader:

 

I start with my this ds trying to convince him that looking at animals in rock pools would be cool (can you see *I* really want to study this) but alas he is not interested. He wants to study how deep the roots of trees go into the soil. :001_huh: I tell him that we could look at this using road cuts, but that perhaps it would be pretty difficult to study. But he does still want to study soil (4 months ago, I read 30 minutes about soil profiles to him, so I am pretty surprised he remembers anything). So we review what we know about soil: layers A,B,C; earthworms, and that is about all he knows. We go to the library and find no books on soil in the kids section and 2 books with a chapter on soil profiles and topsoil composition.

 

The next day when I am out for a walk in the early morning with a friend, I look at the road cuts and notice different layers in the soil. Perhaps we can identify the soil profile using these cuts. I tell ds, and he loves the idea. He packs a backpack and brings a tape measure, a "data collection booklet", a broken pencil :001_huh:, and a trowel. We go to his favorite spot where he digs out "mudrocks" and loves to throw them and watch them smash. I am wondering what a "mudrock" is from the point of view of a soil strata. We get to the site, and start measuring and recording and then promply cannot remember anything about the different strata and how to identify them:lol:. So back home we go, look up the info in the older ds's textbook, take some notes, and go back out. We measure the strata and feel pretty confident.

 

Next, we walk around the woods looking at the different cuts and their strata. Our woods is on a small mountain (large hill) and it was used 100 years ago as a sheep farm so there are lots of old wagon trails that were cut out of the hill side (think Lord of the Rings Weathertop and "get off the road" scenes, because they were filmed 200m from my house). What really really surprises us is that the soil profile just along this one road cut is very different. Top soil thick to non-existant, B horizon 20cm to 150cm deep, or even areas with bedrock exposed. Funny how I have never noticed this before.

 

So, now I ask *the* question: Why? Why is the soil profile different in different areas? We brainstorm a few reasons (I guide him here, but some he comes up with on his own): Slope, vegetation, bikers. He suggests (on his own) that pine trees inhibit the growth of plants under them so that there would be less topsoil where pine trees grow. !!! Excellent thinking and really cool hypothesis. He also suggests that the B horizon is thicker in some areas because in ancient times more soil collected and then over time compacted into b-horizon soil.

 

so.... WOW, this is going to be an AWESOME project. How does the slope and vegetation of the mountain affect the amount of topsoil? If he were 11+, he could win the regional science fair with this one. (or is it that *I* could win? :lol:)

 

Time: 2 hours

 

Ruth in NZ

Edited by lewelma
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That's REALLY cool. I've been wanting to do project-based work with dd but I felt like she needed a foundation in the basics first (an initial series of life/chem/earth science). Did you just start from the beginning teaching science *through* inquiry, or did you establish a base of knowledge first?

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Did you just start from the beginning teaching science *through* inquiry, or did you establish a base of knowledge first?

 

No, I do not teach science through inquiry. We read directly about scientific principles, rather than uncovering them through inquiry-based activities. We spend 3 terms reading and watching docos, and then 1 term on an investigation. We follow the WTM's suggesting of 1 field of science each year: Biology, Earth/space, Chemistry, Physics. Within each field, I choose 3 subtopics to study for 9 weeks each. For Biology in 5th grade it was genetics, evolution, microbiology (his choices) and for 2nd grade it was zoology, botany, and ecology. Then we spent the last 9 weeks applying what we have learned to a specific area of study.

 

This year for Earth/Space Science, both children have done units on Astronomy, Geology, and Oceanography. Now, one child will be doing an investigation on Oceanography (waves) and the other on Geology (soil).

 

Having spent time reading, watching docos, and studying about the 3 subtopics, they have informed ideas as to what would be interesting to study. The 6th grader already knows a lot about waves, tides, and shorelines because his text book spent 20 pages on it. This knowledge allows him to delve more deeply into the research project and come up with an original question and research.

 

HTH

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No, I do not teach science through inquiry. We read directly about scientific principles, rather than uncovering them through inquiry-based activities. We spend 3 terms reading and watching docos, and then 1 term on an investigation. We follow the WTM's suggesting of 1 field of science each year: Biology, Earth/space, Chemistry, Physics. Within each field, I choose 3 subtopics to study for 9 weeks each. For Biology in 5th grade it was genetics, evolution, microbiology (his choices) and for 2nd grade it was zoology, botany, and ecology. Then we spent the last 9 weeks applying what we have learned to a specific area of study.

 

This year for Earth/Space Science, both children have done units on Astronomy, Geology, and Oceanography. Now, one child will be doing an investigation on Oceanography (waves) and the other on Geology (soil).

 

Having spent time reading, watching docos, and studying about the 3 subtopics, they have informed ideas as to what would be interesting to study. The 6th grader already knows a lot about waves, tides, and shorelines because his text book spent 20 pages on it. This knowledge allows him to delve more deeply into the research project and come up with an original question and research.

 

HTH

 

Thanks!

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I enjoy your posts on this too. We have been following WTM recs and doing one science fair a year too, but my project ideas are not so good. It is the hardest part for me. We usually try to find one project that we have been working on at home from our science experiment books and expand on it. I think the topics have been a little boring (shh don't tell the kiddos I said that!) so far, but we have all learned so much from each one still. And they get so much out of the fair itself beyond science like public speaking, answering questions to the judges, etc.

 

Your topics sound fascinating! Keep up the posts, if you have time, so we can keep up. You may give me somethings to think about for next year.

 

Unfortunately our fair always falls mid year, so I feel like we haven't covered enough of the topics to have a good grasp on it, but I have some ideas for next year.

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Week 2

 

6th grader

 

We take monday afternoon to go to the beach. We pack the sand and magnitite we collected last week, a long meter stick, a shovel, a stopwatch, and his notebook. We also print a copy of the Beaufort scale for wind speed based on the surface characteristics of the sea. The boys will be going in the water so they put on their wetsuits and bring goggles. I plan to stay dry!

 

Today's goal is reasonably simple. We want to find out if we can measure sand movement and if the sand we collected is different enough in color to stand out. Also, we will be looking to see what other tools we will need for his research. We head to the beach, hopeful of a good outcome. In the car we review what we want to measure.

 

When we get to the beach, we measure:

 

Wind speed with the beaufort scale. We realize that the written descriptions we have are not all the helpful and we need photos.

 

Wave height. This is difficult because it really depends on where you measure the wave: at a certain distance from the shore or depending on each individual wave and then is it the swell, crest, break, etc? He decides that he will measure 3 waves at their breaking point and average the wave height.

 

Wind direction. He can throw up a piece of dune grass but we can only approximate the wind direction. We need a compass.

 

Slope of the beach. To do vertical measurement down for each meter horizontally, we need a level.

 

Direction the shore faces. Need a compass

 

Tide: We needed to look at tide table before we came. We see that it is lower tide than it has been, but we don't know if it is in or out.

 

Now the excitement happens.....We measure the movement of the sand. The sand he has collected it whiter than the sand on this beach, for which I am very thankful. We will not need the magnetite, which is great because it is sooooo time consuming to collect. In a flurry of excitement, he takes a scoop of sand and goes up to where the waves are washing up on shore and puts the ruler down and when the wave hits it, he realizes that his ruler is going the wrong direction. He takes another scoop with the ruler the other direction and the sand is hit by the wave and goes right out to sea. One more time and he thinks it moves 20cm to the right. We discuss that putting the sand right at the shore line might result in more info about wave action than the lateral movement he is really interested it. So he heads out to sea.

 

He measures a 1m long step and takes 10 steps out to sea with his brother. He is waste deep, and 8yo is more like chest high. Older DS instructs younger to hold the ruler with his feet under the waves as he takes a scoop of sand and tries to dump it on the ruler. (I'm a bit concerned that the nice metal meter stick will be heading out to sea!) Then, he puts on his goggles, holds his breath, and watches the sand move for 1 minute while I time. Yes, he can see it move, but is uncertain how to measure it. He tries this 3 more times. Then he comes back in and we talk about how he is measuring and how he can improve it. He decides that the shovel of sand starts to move before he even gets it to the sea floor, so he really should have a enclosed container to release the sand at depth. Also he needs more sand to make a good measurement. We also discuss how he is measuring movement. With a clump of sand, is it ALL moving in one direction? Is some spreading the other way? Is he dumping it on the ruler or next to it? How will he be consistent and honest in his measurements?

 

We make up the list of tools we need to bring next time: compass, container with lid, photos of Beaufort scale, tide tables, and a level. Then they go out and play in the surf for an hour :001_smile:.

 

On our way home we discuss independent and dependent variables and proximate and ultimate causes. The wind and tide affects the waves which affect the movement of the sand. The movement of the sand is dependent on all the other variables we are measuring. We also discuss how the wind might affect the movement of the sand differently at the other end of the bay where it is not diagonal to the waves, and that the rocks nearby might affect sand movement on the other side of them. We consider these as possible research questions. We also decided that, YES, this project is doable!!!!

 

The next day, we begin research on this topic. He looks up search terms like sand movement, beach erosion, wave refraction, and long shore transport. He decides he is interested in long shore transport. He reads the Wiki and then looks it up in the online Encyclopedia Britannica. We also realize that the book we found last week on seashore ecology has an excellent chapter on the details of long shore transport (like 20 pages) so it is his goal to read it over the next few days.

 

Time: 1.5 hours at beach, 1 hour discussion, 1 hour research, 2 hours reading. Total: 5.5 hours.

Edited by lewelma
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Week 2: second grader

 

We head out with his backpack packed with a trowel, a small ruler, a protractor, his data collection notebook, and a *sharpened* pencil, water, and a snack (because 8 year olds cannot last for >1 hour without food!) We also bring the meter stick. The boys argue over who gets to carry the meter stick as it is great for whacking bushes!

 

We go back to the location from last week and try to measure some details about the area. The leaf litter is mostly pine straw, but there is some underbrush here. He thinks it is kind of thick. We try to estimate the slope of the location and immediately run into trouble. Are we measuring the immediate slope (like the closest meter to the wagon-road cut) or are we measuring the general slope of the hill like averaged over 10 meters? We try the longer slope. DS8 runs up the hill and puts his head to the ground and sites the meter stick. DS11 takes 1-meter wide steps to get to younger son. They decide it is about 1 meter up for 7 or 8 meters across. We try something different. We try to use the protractor to measure the difference between the horizontal and the estimated rise of the hill. We get 30 degrees, but this number is not a great estimate. This will be a problem. DS8 is ready to move on.

 

We go to the area where we found exposed bedrock on a bike trail last week. We measure the soil strata about 5 meters away from the bike trail and it is clear that the bedrock is an outcropping, maybe worn down a bit by the bikes, but not completely. DS11 looks around the area and finds about a 3 by 8 meter area of exposed bedrock. interesting.... DS8 tries to measure the undergrowth and decides that this area is thick and the last area was moderate. We clearly are going to have to standardize this. I am thinking photos with rankings that we bring with us for evaluation of new sites.

 

Now, younger ds wants to go "bushbashing" to an old wagon trail that is no longer in use and has been overgrown for clearly 60 years because of the trees growing in the middle of it. They know about it from explorations with the 'woods club." I am not too pleased, because I am not really wearing the right shoes. :001_huh: So we scramble down, and I suggest that we take a top soil sample right in the middle of the wagon trail, because then we could see how much top soil has collected over 60ish years. We start digging. and digging. and digging. ...... I am getting hot and annoyed. How deep is this top soil anyway? We don't get to the bottom of it but it is 16cm so far. (other 2 locations on slopes are 5 and 6 cm). We decide to come back with a larger shovel. (I'm hoping this will not get me in trouble: carrying a large shovel in a public park!?!? )

 

We continue down the overgrown wagon trail and ds decides to do another road cut measurement of strata. The top soil is only 1 cm, and the 1m slope is 45 degrees! We have trouble with the deeper strata because dirt has slid down the slope and we have to dig it out. The sand flies are biting and biting and biting, and then ds says "I'm bored, lets go home." We all agree. We really need a large shovel. We scramble out of the woods, I twist an ankle, a shoulder, a hip, something. We get home. Time for a cup of tea. The boys go find a book.

 

For the next outing we need a shovel, and some way to conceal it.:D

 

Time: 1 hour. Plus 30 minutes to get all the dirt out from under my fingernails.

 

More next week.....

 

Ruth

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Thank you! I'm always amazed and overjoyed when kids kind of just figure things out on there own! I love to watch those wheels churning! Thank you for your posts....I feel inspired now to do the same with my kids! I look forward to seeing more.....if you get time....

:001_smile:

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For the next outing we need a shovel, and some way to conceal it.:D

 

Time: 1 hour. Plus 30 minutes to get all the dirt out from under my fingernails.

 

More next week.....

 

Ruth

 

:D Perhaps with a hat and a long jacket it could be a "fourth" member of your outing? Maybe your youngest could tie a bandana on the end filled with "essentials" and play at "running away from home"... :001_smile:

 

I am going to refrain from commenting on every post, but please be assured that I am VERY interested. Thank you for taking the time.

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:D Perhaps with a hat and a long jacket it could be a "fourth" member of your outing? Maybe your youngest could tie a bandana on the end filled with "essentials" and play at "running away from

home"... :001_smile:

 

:lol: These are just the kind of ideas that my 8 year old would love!

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Week 3. 6th grader

 

Ok, I have just re-read this post, and it is long and complicated! There is more experimental design in here than most non-scientists ever see. I hope that it will help some of you understand how science works. (This is just to tell you that I might have gone overboard :tongue_smilie:)

 

Before we do any more observations of sand movement, we need to do some thinking. He still does not have a clear cut hypothesis because he really does not yet know enough to have one. We have 2 goals for this week: one is to start designing the experiment even though we are not totally clear on the final hypothesis. The second is to go back to the ocean to learn more about long shore transport to help inform the development of his hypothesis.

 

Goal 1: On Monday, we discuss his experimental design, this takes a lot of thinking and requires a few tables.

 

We learned last week that the dependent variable (sand movement) is measurable. So the number one thing we need to think about now is how we are either going to vary/control the many different independent variables: wind speed, wind direction, wave height, direction of the bay, obstacles, gradient, and tide (in/out, high/low). I know, but he doesn't, that with this many variables there would be a HUGE number of combinations and with replications within each one, we would have to go out about 1000 times. So, I want to guide him through the process of figuring this out on his own. I suggest 3 things: that he 1) chooses 3 variables he wants to study, 2) figures out how he will measure them, and 3) makes a couple of tables to see whether he can vary that many variables given the time he has.

 

First, given what he has learned so far, he chooses wind speed, direction of the bay, and tidal direction as factors that might affect long shore transport. He thinks that when the wind and the tide are in the same direction the long shore transport would be augmented. We also discuss when the tidal movement would be the strongest, and decide that mid-tide would have the most movement. We discuss whether he can control the other variables. Gradient and obstacles are easy, just go to the same spot for measurements. Wind direction is easy, we just only go out when it is a Northerly. Wave height cannot be controlled. So what are we going to do? This is where we discuss why you replicate. If you replicate enough, you can overcome the variability in variables you cannot control.

 

I also spend quite a bit of time discussing “effect size.” If you expect a small difference between groups and lots of variability then you need lots of replication. If you expect a large difference between groups and little variability then you need less replication. For example, if you want to know if men or women are taller, you probably only need about 10 people. If you wanted to know if Maori women are taller than Caucasian women, you might need 100 people, because they are similar in height. This makes sense to him. The question then becomes what effect size are we expecting, and this is where preliminary data is very important. We don't have enough yet to determine this. So the replication needed is still unknown.

 

Second, we discuss how he will measure the variables. Will he have 9 wind speeds using Beaufort wind speeds 1-9 (probably not 9, because he could drown!), or will we have low, medium, and high wind speeds for Beaufort speeds 1-3, 4-6, and 7-9? He wants to do 9 wind speeds, so I have to explain to him how many times he will have to go out. 9 wind speeds, 2 study sites, and 2 tidal directions and at least 3 replications within each is >100 cold-water visits. Brrrrrr. He begins to understand the idea of grouping. He decides on 2 wind speeds 1-3 and 4-6, and decides not to go out in very high wind (which Wellington does get). So now, he has 2 study sites, and 2 wind directions (N and S are the prevailing winds by far, like 99%), and 2 tidal groups (in and out). We discuss discreet vs continuous variables, and I ask him how he would graph each result. He guesses correctly, you use bar graphs for discreet variables and scatter plots or line graphs for continuous variables.

Third, we are finally ready to draw out the chart of all the different samples that we need. Because there are 3 variables, he needs two tables. They look like this:

 

East facing Bay, North wind. This is a 2 by 2 grid:

Tide (in and out) by wind speed (low and high)

 

North facing bay, North wind. Also a 2 by 2 grid

Tide (in and out) by wind speed (low and high)

 

Within each of these 8 combinations he needs 3 replications: so 24 days, except he can collect the 2 bays on the same day, so only 12 outings are required. This is doable. Given that we need certain wind speed and direction for each combination, we need enough days for this to happen. We also decide on 3 replications within each day that we measure. So next he draws the data collection table. The columns are:

 

Date, bay, wind speed, wind direction, tide, wave height, direction of sand movement, cm moved (1), cm moved (2), cm moved (3), average cm moved.

 

Goal 2: On Tuesday, we go out to the beach.

We check the tide table and go at mid-tide. It is cold today, so we bring long johns and wool hats in addition to wet suits. We have to collect more sand and so swing by the other beach. As we collect, a woman walking by with a preschooler, tells her little one that “no, they are not taking the sand home.” I realize that although I do not think it is illegal to collect sand, if everyone took the sand for their sand boxes it would be a problem. However, we are only moving it to another beach. I discuss this gray issue with my boys, and we decide that what we are doing is ok, but perhaps we need to go early in the morning when no one is there.

 

Now that we have the sand, we drive to the study site beach, and we choose a location on the N facing beach that is not near any obstacles. This is the first time on this beach; last week it was the E facing beach on the same bay. We realize that the wind is coming from the South (Antarctica), which is not in our experimental design. Oops. But we are already out there, so we collect some data at this new study site. It is protected from the wind, and we find that the movement of sand is basically nothing. About 1 cm in 1 minute. Then, we go to the E facing study site and find the sand is moving somewhere from 4 to 10cm in 1 minute . Wow. Big difference. Also, the sand is moving in the direction of the wind- the opposite direction from last week! Hummm, that was not in the experimental design that we just did, but clearly wind direction is critical.

 

Another couple of problems creep up. Ds(8) who is in up to his chest refuses after 4 measurements to go out again to hold the ruler. :001_huh: It is just tooooo cold. With 2 more measurements to go (3 per study site), ds(11) has to figure out how to hold the ruler, dump the sand, and measure its movement without help. We think he can do it, although it is difficult. This highlights another problem, we are heading into winter, and the water is only going to get colder.

 

Finally, ds mentions in passing about the sand moving both directions, and he is only measuring how far it is going in one direction. I am not out there in the water, so I don't really understand. He starts drawing diagrams in the sand of how the sand spread and drifts. We decide he needs to measure movement in both directions and then subtract the 2 to get directional movement. So has he done this with all the data we collected today? He says he has. I am not so sure, so we have a discussion about the honesty required by scientists even in the face of having to recollect the data. He sticks by his original assertion that the data is valid. ok. Finally, I throw out an idea. Could he keep track of the number of days with N wind vs S wind and actually predict how much long shore transport happens over 2 months at the 2 different locations? Something to think about.

 

We finally get home, and put ds(8) in a hot bath and feed him hot chocolate afterwards. I rinse out the bathing suits, towels, wet suits, goggles, then hang them out to dry, and realize that the clean up is going to be a pain in the neck!

 

Discussions: 2 hours

Experiment: 1.5 hours

Reading text: 1 hour

Total 4.5 hours

 

Wow, this has gotten really really long and complicated. If anyone has any questions, I'll try to explain better. This part of the scientific process is usually the most difficult which is why I described our thinking in such detail. The next posts won't be so long, I promise.

Edited by lewelma
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Week 3. 2nd grader

 

We head out on Monday into the woods to finish digging that hole. I wear proper shoes :001_smile:. We bring a big shovel and just hope no one sees us. Our goal this week is to get a measurement of topsoil on a flat area so that we can start to compare it to the road cuts that we can see on the hill sides.

 

I start digging with the big shovel, and after about 10 minutes, I have hit so many roots that I really can't dig properly. The 8 year old wants to get hedge clippers to help. We agree, and the 2 boys go back to the house to get the clippers. I keep digging. In the end, the clippers don't really help much, we just have to enlarge the hole to work around the roots. It takes 30 minutes total. The top soil measures 30cm! But we run into a major problem. It is virtually impossible to tell when the topsoil changes to the “e” layer. The e layer is a bit more crumbly and rocky and has less moisture. But when you are sliding the shovel down, you move the dirt around and also soften the crumbly e layer so that you can't see the crumbles. This is really a problem. We try to feel it with the shovel, look at it with our eyes, and compare it to the layers we have seen elsewhere. This is going to be tough. We decide that we need to play around with the topsoil and e layer in the road cuts, to see if we can distinguish between them when they have been disturbed.

 

Next, ds wants to measure the top soil on a really steep area away from any road cuts. He measures only 1 cm of top soil. He then starts to wonder if he should be measuring the soil vertically or perpendicular to the slope. Humm. Good question. We decide that the road cuts are vertical, so that to stay consistent we should measure vertically all the time. Then he tries to measure the slope. This is really difficult. Both boys work together and fight :001_huh:for about 10 minutes about the best way to do this. The lay of the land is not perfectly smooth, and the smallest undulation causes major changes in the slope. Plus, holding the meter stick horizontally while the other boy measures the angle with a very small protractor seems a method doomed to inconsistencies. We need to develop a large tool of some sort, perhaps with a weight hanging vertically with gravity.

 

Overall, a pretty easy week. But now we have information on both the slope and the flats for the next step. We are ready to make a hypothesis and design an experiment.

 

Data collection: 1 hour

Total time: 1 hour

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We finished our project (with "preliminary data") and presented it at the science fair, where it was a hit.

 

I'm hoping though, to find a different science fair next year, or maybe an additional one. It would help us a great deal if the fair was held later in the spring. Also, our homeschool group heavily skews toward the younger set, so my 10 yo is already one of the oldest in the group to do a science fair project. He loved his project and learned SO much, but many of the children at the fair were just too little to understand what it was about, so he felt it was not "interesting" enough.

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Week 4. 6th grader

 

Over the 4 day weekend (in NZ) we go out 3 times. DH is keen to be involved, so this makes standing out in the frigid water a bit more fun. But first we need to discuss the problem of the wind direction. Given what we found last week, ds wants to add wind direction into his experimental design, but after doing the calculations and realizing that he does not have time to go out 24 times, he decides to drop the tide (in vs out) so that he can add in wind direction. He draws new tables, and we agree to always go out when the tide is going in since this is the condition he has collected the data in already. So now we must control for tide, which restricts when we can go out.

 

Friday morning we go out to the study sites. Luckily, since DH will be getting in the water he can check ds's sand dumping methodology and objective measurement skills. All seems to be ok. I am relieved. DH even takes some underwater photos of the sand right when it is dumped and after 1 minute of movement. These photos will be a very nice addition to ds's poster! It is always nice to be able to reference a photo when describing data collection. We go out 2 more times this weekend and bring some of ds's friends to help with holding the ruler. It is quite fun to involve others in the data collection.

 

Ok, here are the new problems for this week that we must solve:

 

  1. The wind seems to gust a lot at this site. We will mark the wind speed at a 2 and then it is a 4 when one of the measurements is done. Not sure how to control for this. Perhaps take a new wind measurement every 5 minutes.
  2. The current seems to vary vertically. We are being pulled east away from our towels, but the sand at the bottom is moving west. DH suggests dumping sand at the top of the water, and they watch it move east and then west as it settles to the bottom. Interesting.
  3. We check the wind speed and direction before we leave, but the exposed bay has much stronger wind than the protected bay during a northerly. Do we indicate that the protected bay has wind speed of 3? or of 5 but just protected?
  4. We look at some photos of the Beaufort scale on the internet and realize that all of our earlier measurements are inaccurate. We carefully adjust them retroactively (is this allowed in science?)
  5. In one measurement, the sand is swept away in 2 seconds. How do we use this data? Do we discard it?
  6. On one day, the wind was supposed to be from the SE based on the weather report, but it moved West at one site and South at another. How do we record this? Very confusing. It must be caused by the nearby mountains, but how?

  7. On our first high wind day, DS cannot stand in the water and take the measurements. DH is holding him so that he does not fall over. Wind is about 30 miles per hour. How will DS do this without help? He needs 7 more high wind days. We have just hit day light savings time so it is dark by 6pm. Will we have to do all measurements on the weekend and hope we can get the right conditions (wind speed and direction) or do we have to plan to go early in the morning before work so DH can help?

We are have school holidays for the next 2 weeks, so I hope to get quite a bit of data collection. I explain to ds that it will get harder to get just the right conditions for the data he needs as he fills in his table. Plus it is getting colder. I keep saying this, but OMG is it cold in the water! Plus add 30 to 40mph winds and !!!! I really don't want to deal with hypothermia.

 

Ruth

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  • 2 weeks later...

Glad you are enjoying it. It is very fun to write up. When it is all done, I might make it available to those students here who are interested in doing a regional science fair project and don't really understand what to do.

 

We have just finished school holidays and got in 5 more samples! I will write it up when I have some time.

 

We have solved the cold problem. I forgot that I bought him a new wet suit a few months ago when the sales were on. And it is a size too big! This means that he can put it on top of the other one. :D He told me he felt like a sausage and could not walk properly. But it and a wool hat did the trick. The main problem now is that he keeps dropping the cup of sand because he can't feel his fingers.:001_huh:

 

Ruth in NZ

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Glad you are enjoying it. It is very fun to write up. When it is all done, I might make it available to those students here who are interested in doing a regional science fair project and don't really understand what to do.

 

We have just finished school holidays and got in 5 more samples! I will write it up when I have some time.

 

We have solved the cold problem. I forgot that I bought him a new wet suit a few months ago when the sales were on. And it is a size too big! This means that he can put it on top of the other one. :D He told me he felt like a sausage and could not walk properly. But it and a wool hat did the trick. The main problem now is that he keeps dropping the cup of sand because he can't feel his fingers.:001_huh:

 

Ruth in NZ

 

Your posts have helped me immensely in planning out Project based learning themes.

 

I agree, you could write a "How to" book for science projects!!

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I'm enjoying reading along as well, but I must confess that I'm not clear as to the specific aim of each project.

 

Oh, I love questions! Makes me feel like I am not writing into a black hole.

 

If I have not been clear before, here are the 2 questions:

6th grader: How does wind speed and direction affect the longshore movement of sand?

2nd grader: How does the slope of the land and quantity of vegetation affect the depth of the topsoil? (This is newly identified, and I have not written it up yet)

 

Now, I have seen over and over people who think that science is all about a hypothesis that you are testing. Something like "In a north facing bay, I think that the sand will move to the west when the wind is from the north." Then you go out and find evidence to support or reject your hypothesis. There is definitely science (and social science) research that does this, but it is really only about 1/2 of research. In general, research falls into 2 categories: exploratory and confirmatory. My kids' research is exploratory; you have a question, and you try to figure out which factors are important. Confirmatory is when you have an idea of the answer and you try to confirm your hunch.

 

Most confirmatory research is based on reading the literature. There has been LOTS of research done, you read it, and you apply it to a new situation. The previous research informs your ideas and helps you make a hypothesis. The problem is that young students really can't read the research. It is not accessible at all. My 6th grader and I researched his question and were completely overwhelmed with material that was simply not readable. Some of it even I could not read. Although I have a PhD in science, it is not a PhD in oceanography. Science has quite a bit of jargon and takes a lot of time to come up to speed in a field.

 

So a child has a question. He cannot read the literature. He cannot really come up with a hypothesis based on previous knowledge or on other's work. However, he can still do research; it just must be exploratory. The research still controls variables and has replications and a clear-cut experimental design. It is not that the research is not orderly, just that it is not confirming previous work.

 

After my son figures out how the wind speed and direction affect the sand movement in HIS north facing bay, a confirmatory question would ask if what he found in THIS north facing bay is true for other north facing bays. Then this NEXT research project becomes confirmatory. " I have found that in a north facing bay in a north wind, sand moves 3 cm every hour to the west. I hypothesize that this will happen in all north facing bays."

 

We have been working on Art of Argument for our logic this year, and I talked to ds(11) about the importance of the fallacies of Hasty Generalization and Sweeping Generalization. He CAN conclude about HIS north facing bay because he has replicated there. He CANNOT conclude about ALL north facing bays because he has only studied one.

 

Not sure if I answered your question. But HTH!

 

Ruth in NZ

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Oh, I love questions! Makes me feel like I am not writing into a black hole.

It's clear from the enthusiastic response you receive here that you're not writing into a black hole.:)

 

If I have not been clear before, here are the 2 questions:

6th grader: How does wind speed and direction affect the longshore movement of sand?

2nd grader: How does the slope of the land and quantity of vegetation affect the depth of the topsoil? (This is newly identified, and I have not written it up yet)

Narrowing each project down to a question like this is helpful.

 

Now, I have seen over and over people who think that science is all about a hypothesis that you are testing. Something like "In a north facing bay, I think that the sand will move to the west when the wind is from the north." Then you go out and find evidence to support or reject your hypothesis. There is definitely science (and social science) research that does this, but it is really only about 1/2 of research. In general, research falls into 2 categories: exploratory and confirmatory. My kids' research is exploratory; you have a question, and you try to figure out which factors are important. Confirmatory is when you have an idea of the answer and you try to confirm your hunch.

Yes, an important distinction. With school-aged children, the two (exploratory & confirmatory) are understandably intertwined.

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Weeks 5 and 6. 6th grader

 

For the past 2 weeks, we have focused on data collection. It is critical to get this done ASAP because winter approaches. Plus, he is considering a second part to this project! This part would be done inside at the computer in a nice warm house :001_smile:. The science fair is in 8 weeks.

 

The question and experimental design was finally solidified at the beginning of week 5:

 

How does wind speed and direction and shoreline orientation affect the longshore movement of sand?

 

The final experimental design includes measuring sand movement 3 times at a north facing beach and 3 times at a east facing beach each time we go out. He will go out a total of 12 times: 3 times in high speed northerly winds, 3 times in low speed northerly winds; 3 times in high speed southerly winds, and 3 times in low speed southerly winds. He will control for tide by only going when the tide is coming in.

 

In the last 2 weeks he has collected 4 more samples. Here are the new problems and his solutions:

 

The main difficulty has been differentiating between the global wind speed and the local wind speed. The local wind speeds vary drastically between the 2 beaches even though they are on the same bay and are only about 1 mile apart. He has decided that part of what he is curious about is the sheltered nature of each bay depending on the wind direction. So he has started recording the predicted wind speed from the weather station, and has tried to confirm it by evaluating the wave situation in the middle of the harbour (using the beaufort scale). This is a bit tricky because we are far away, but the number of white caps is pretty easy to see. Luckily, we know that the first 3 measurements he did were all global low wind southerlies, so we can retroactively include that data. He has been recording the local wind speed from the beginning.

 

The next big surprise came when he got very little movement of sand and in varying directions in a high wind northerly on the north facing beach. The past 2 measurements were strongly to the west. So what happened? We brainstorm some while we are collecting sand at the more sheltered beach and decide that if the North wind is slightly NE or NW or straight on, it would affect the directional movement of the sand. This effect would not happen at the east facing beach because slight differences in direction of a Northerly would still push the sand to the south. We go back to the North beach and measure the direction of the wind very carefully, and plan to do this from now on. The problem is that he has not done this for the prior 2 high wind northerly measurements, so we decide to add additional visits to the ocean for a few more high wind northerlies :tongue_smilie:so we can figure out this more complex relationship between wind direction and the direction of the sand movement.

 

Then, today he had quite some difficulty with the data collection. The wind speed measured as a 6, which is 30mph, and the wave action was so big that neither my ds nor my dh could even see the ruler. So after much brainstorming, the decision was to use my dh's foot for a measuring device, to dump white shells instead of sand, and to only measure for 30 seconds. They did get 2 measurements this way. So we talked about how this data would be different than the other data. That he could use it, but would need to indicate the implications of the different measurement methodology.

 

Then in the car on the way back, I asked ds to brainstorm ways to graph his data. He came up with some nice line graphs for the basic data, but the north facing beach in a northerly is more difficult. He needs to come up with a way to put wind speed and direction and sand speed and direction all on the same graph. I told him about vectors, and he plans to start sketching some ideas tomorrow. I want him to puzzle over this for a while, because often it can be quite tricky to *clearly* present your data so that the conclusions are obvious.

 

Finally, ds has a bit of a melt down one day last week. He knew the water was cold and started to wish he had chosen a different project. This is not unexpected, I have yet to get in that cold water! :ack2: But from the point of view of being a scientist, this is a very very valuable lesson. The lesson is two fold. (1) you need to be realistic when choosing a project. It must be doable physically and intellectually, and within the time and money restrictions. But (2) science throws you curve balls all the time. Even with all your planning, things go wrong, seriously and terribly wrong all the time. And you must be able to roll with the punches. You must problem solve and find a way if it is possible. Luckily for this particular situation, I remember that I bought him a size-up wetsuit a few months ago which he can wear on top of the other one which is on top of his polypropylene long johns! Today, he was toasty warm in the water and played in the surf for an extra 30 minutes!

 

So the goals for next week are to 1) lay out a schedule, 2) read all the regional fair regulations, 3) keep collecting data when the wind is right, and 4) design part 2 of the project,

 

Part 2 of his project concerns predicting if the sand is moving one direction or another over the period of a month. He has found that the direction of the sand movement depends on the wind direction, and the distance depends on the wind speed (although a bit more complex on the North bay in a northerly). He can get the global weather conditions from the weather service, and if he can correlate them to the local conditions that he has measured, he should be able to hypothesize the winning direction. We need to flesh this out.

 

Data Collection: 8 hours (includes driving to and from the beach)

Discussion: 1 hour

Total Time: 9 hours over 2 weeks

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Weeks 4, 5 and 6. 2nd Grade

 

Well, not much has been done for the past 3 weeks. We were on school holidays for 2 of them, but really it was because I was focused on getting his brother's ocean sampling done before winter!

 

DH spent an hour last week planning out what needed to happen in the next 7 weeks before the science fair. They laid out a time line for the data collection, making table, drawing graphs, writing intro/method/results/discussion, printing photos, labelling photos, making title, sticking it down, designing the presentation, and practising the presentation. Really it took up the whole 7 weeks with only 2.5 weeks for data collection (ds is a slow writer). So we need to get going on the data collection!

 

So, today I spent an hour helping ds design his experiment. He was pretty clear that he wanted to study both slope and vegetation and how it affected the topsoil. So I started asking questions. What about the topsoil? composition? depth? Definitely depth he decides. Ok, what about the vegetation. Definitely high and low vegetation. So we draw up a 4 way chart with high slope/flat vs high/low vegetation. We take his 5 samples to date and try to put them into the chart. Immediately, we run into trouble. What I consider high vegetation, he thinks of as low vegetation. :001_huh:

 

We take about 20 minutes to decide the vegitation question. How do you define high vs low vegitation. We consider: 1) can you see the sky? 2) is there underbrush? 3) how large is the area with no underbrush around your sampling area 4) are the deciduous or evergreen trees overhead? What a mess. He finally decides that high vegetation will be deciduous trees with heavy undergrowth within 2 meters of his sample and low vegetation will be pine trees with no undergrowth. I make it clear that not all parts of the forest will be able to fit into these 2 categories. He is ok with that. So his final question is "how does slope and vegetation density affect the depth of the topsoil?"

 

The next problem we discuss is how to measure the slope. My dh told me last week that the ancients had tools for this that are easily found on the web that we could replicate. I begin to discuss this with ds and start to draw some of my ideas, and he interrupts me. I begin to get cross, and then remember, this is *his* project. Maybe it would be a good idea for me to listen to his ideas! :tongue_smilie: He SHOCKS me and draws the most amazing invention to measuring slope. I wish I could do it justice here, but believe me, it was better and simpler than mine. Glad I kept my mouth shut. I properly congratulate him and circle and label his diagram for future reference.

 

So, we set some goals for this week. We need to get digging. As discussed in an earlier post, we need to study disturbed topsoil to see if we can differentiate it from the lower soil strata. And we, obviously, need to start collecting data. He plans to start this weekend.

 

I might add, my ds8 is a real cutie. Just so cuddly. I love doing science with him because he is so sincere and dedicated. I.just.love.it.

 

Planning: 2 hours this week (we took 2 weeks off)

 

Ruth

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Week 7. 2nd grade.

 

The focus this week is data collection. The first thing we need to do is go to the 5 locations where we have already dug holes and check the slope of the land using his new invention. We have slope estimates, but they were really inconsistent because we didn't have a good tool.

 

We build his invention with a meter stick, string, and a weight (2 magnets). We mark off 2 cm marks on the string that will hang down. The string slides through the hole in the meter stick so you can pull it up. Now all we need is a level, and we realize that we don't have one (I thought we did). So I suggest that we use a long flat container full of water, draw a line on it, and use it like a level. We try this and realize that we can't really see the water easily, so I decide to color the water with coffee. :lol: So we head out into the woods with a shovel and pitchfork (sort of concealed in a bag), the measuring device, the data notebook, and the container of coffee. We realize quite quickly that the coffee is leaking.:tongue_smilie: and that the magnets at the end of the string keeps falling off. We search multiple times in the leaf litter for the missing magnets:tongue_smilie:. Then the coffee spills on ds(11)'s shoe while we are climbing up a steep slope and he is NOT happy:tongue_smilie:. Believe it or not, we keep at it for more than 1.5 hours in 45 degree weather!!!!

 

During our digging on a flat area in the woods, we come up with a great new idea. We notice that on a slope, there seems to be a lot of leaf litter collecting on the upward side of the plant. We decided to dig a hole there because we expect the soil to be quite deep. ds(8) and I dig down about 25 cm, think we hit the e-layer, measure, and fill the hole in. Now something VERY important happens from the point of view of understanding science. My older son tells us that he wants to re-evaluate the measurement. He re-digs the hole! :001_huh: At the time, I did not know that he had looked at the data sheet and found that the hole was not as deep as the previous hole. Once I realize what is going on we have a very LONG conversation about why scientists do "double-blind" studies. It is not that scientists would purposefully change data to fit their assumptions, it is more that your expectations subconsciously affect your data collection to sway it towards your expectations. Unfortunately, for this very important point, my ds(11) is correct and we had not hit the e-layer but rather just a big rock that started to crumble. So the topsoil is 5cm deeper than our first measurement. We decide that we need to look more carefully for rocks. And then we realize that the coffee has tipped over and completely leaked out. It is just one of those days!

 

So a few days later, ds(8) and I go out by ourselves to do some reconnaissance. We won't be digging, just finding some good locations. The first thing he wants to do is show me a cliff in the woods. We get lost. When we finally find the cliff, I did not realize he was talking about the old quarry. As I look up a 10 story high cliff, I tell him we might have some trouble measuring the top soil. :D But then we notice some really interesting things, one side is lush with new growth, the other is barren. We hypothesize that it is due to one side being shaded from the sun year round. We discuss lichen, cracks in rocks, sliding soil from the top, slope, wind direction, and seed dispersal, and how all these factors interact to affect soil production and vegetation density. Next, he wants to go to a ridge line that he likes. We climb to the top and there is NO topsoil at all. But around the edge, there is grass holding some topsoil. Why? What has caused all the grass to leave the inner portion? I suggest herbicide, he suggests wind. We move to the next path he is interested in. The land near by is lumpy and undulating. We start to apply what we have learned from the cliff. Perhaps as the forest grew, certain areas were shaded, stayed moister, and developed more topsoil. As we wander through the woods for 1.5 hours we find more and more things to wonder about with soil, lay of the land, moisture, and vegetation. And then my darling little boy turns to me and says the most profound thing. "Mommy, you could study soil your whole life and still not answer all of these questions." Yes! YES! This is a point that most people NEVER come to. They have never spent 2 months of their life trying to answer a tiny question only to realize that there are so many questions. Each scientist works for a lifetime on one minuscule area of science; most non-scientists just don't ever get how or why you would get SO specialized. Then my ds says, "It makes me feel so small." And I just give him a big hug. Time to go home and have a cup of hot chocolate.

 

Data collection: 1.5 hours

Reconnaissance: 1.5 hours

Total: 3 hours

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Week 7. 6th grade

 

This week was a disaster. He has 4 samples to go: high wind southerly and 3 low wind northerlies. And we got that high wind southerly this week, straight from Antarctica. Because of the tide table, we have to go out on the 2nd day of the storm.

 

Problem #1: The wind speed is so high (40mph) that all the sediment has been stirred up. He can't see the bottom.

 

Problem #2: He can't stand up in the breakers, and I am a bit nervous to send him out by himself past the breakers where the sediment might be less stirred up.

 

Problem #3: His feet get completely tangled in all the sea weed that has been pushed into the surf.

 

Problem #4: He comes in from the ocean and notices a sign reading "do not swim after a large storm due to pollution risk.":eek: He freaks. I tell him he will be ok because he has only put his head in once.

 

Problem #5: We lose the meter stick!

 

Problem #6: When we go out the next day for a low wind northerly, the sediment is still stirred up! And he can't see the bottom.

 

He spent more than an hour each day working hard to get some sort of measurement. Could he see shells? Could he use wood instead of a meter stick? Could he shift down the beach to avoid the seaweed? Can he go out a bit further? Can he view from the dunes a place where the water is clearer? All the permutations take FOREVER to evaluate especially because it is blowing a GALE. And all for naught. Lesson learned, we need to be out on the first day of a southerly storm before it all gets mucky.

 

Very frustrating.

 

Data Collection: 3.5 hours

Total time: 3.5 hours + 2 hours cleaning up the car, the wetsuits, and the children.

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I think they are learning more in the frustrations than they are with the successes. That is interesting to me. I think it is a huge lesson to see that there are a million unanswered questions, a bunch of days that just won't work, and at the end of it you will STILL come away with more knowledge of the world in general than when you started. Keep up the good work. I can't wait to see how this all comes together.

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And then my darling little boy turns to me and says the most profound thing. "Mommy, you could study soil your whole life and still not answer all of these questions." Yes! YES! This is a point that most people NEVER come to. They have never spent 2 months of their life trying to answer a tiny question only to realize that there are so many questions. Each scientist works for a lifetime on one minuscule area of science; most non-scientists just don't ever get how or why you would get SO specialized. Then my ds says, "It makes me feel so small."

 

:001_wub::001_wub::001_wub:

 

Jackie

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Week 8. 6th grade.

 

We spent this week continuing to collect data and beginning to write it up.

 

After waiting a few days for the stirred up sediment to settle, we finally got one more high wind northerly. Because the surf is so high on the north facing beach, this data is very difficult to collect because he has to get the ruler and the sand on the bottom without the waves washing them away. After 25 minutes of jumping the 1.5- 2 meter waves with a meter stick and a small buck of sand in his hands, he finally gets 30 seconds of data. He told me later that he was holding/placing the ruler with his toes which was really hard to do because he could not feel his feet! He could not use his hands because he was holding the sand! And he explained that the buoyancy of 2 wetsuits made it close to impossible to get down to the bottom to dump the sand on the ruler. This explained the huge kicking for 20 seconds that I saw as he tried to get down to the bottom before the next wave. Since all of his data collection is for 1 minute, these 30 second samples will be doubled to be comparable, and then footnoted. He could not get a full minute sample because of the huge surf. He did get 2 samples which were very similar and verified the consistency of his data collection methodology. I got a video this time, and the wind was high enough to have a windsurfer nearby doing flips. Very fun footage.

 

We read the regional fair requirements finally and realized that he needed to change his notebook slightly (should have read the instructions first!) So we spent 3 hours this week, moving some stuff around (cutting and pasting), making headers, drawing diagrams, and writing up his methods. He also began to analyze his partial data; he realized that his first sample was not done properly and needs to be redone. So he still has 4 samples to go. He has 8 he can use, 2 preliminary, and 2 unusable because of poor visibility. Each of these samples represents 1.5 hours of effort not counting clean up!

 

Next week, he needs to finish the methods and diagrams, collect more data, and start working through possible ways to present his data. I also would like for him to write up a list of problems he has encountered and his solutions because there have been a LOT. He will continue to record the daily weather conditions for the second part of his project.

 

Data collection: 1.5 hours

Write up / notebook organization: 3 hours

Total: 4.5 hours

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Weeks 8 and 9. 2nd grade

 

So ds's project is getting kind of messy. First he was studying the affect of slope and vegetation on soil depth, then we dropped vegetation because we could not be consistent. Then, after digging next to an plant on a slope, he added studying "obstacles" to soil depth. Then, when we did our reconnaissance we noticed orientation to the sun, moisture, and wind. Finally, this week we realized that there are big obstacles (trees, boulders) and medium obstacles (bushes, logs) and small obstacles (sticks, weeds). The depth of the soil really depends on how all of these things interact together. Are you measuring near a medium obstacle that is on the topside or bottom side of a big obstacle? So how in the world are we to make sense of what we are finding? Every time we looked around, we found more factors affecting the soil depth. What a mess.:tongue_smilie:

 

Now let me be clear, this happens in science. Even in high-level, fancy science. So how do you dig yourself out? There are 2 main things that you can do.

 

1) Make your question more general. Basically, we did not know enough about soil to narrow the factors affecting it down to 1 or 2 to study. This often happens with young kids. They get so excited about all the ideas and possibilities that they don't want to focus on something small. And who cares? They are little. In professional science, a scientist would have already read countless articles that would have clarified what was already known and allowed him/her to create a clear cut hypothesis to test. Alternatively, if there is very little literature, then you do exactly what we have done, which is go out and gather a lot of observations and start to think and make sense of the situation. Then, you would set up a study. But ds is 8. So his question now is officially: What factors affect topsoil depth? Very straight forward, and it allows him to include everything he has learned or even hypothesized about.

 

2) The next thing you do is start analyzing whatever data you have collected to date. This will help clarify your thinking and will guide the rest of your data collection. So we spend about an hour per day for a week making tables and graphs (he is a very slow writer). These items he can use on his poster, which also makes him feel good. So he makes the following:

a) Table: slope vs soil depth

b) Scatter plot: slope vs soil depth

c) Table: soil depth for obstacles/no obstacles (taken from samples where the slope is very similar)

d) tomorrow we will graph this table

e) diagram of his slope-measuring device

f) diagram of how large, medium, and small obstacles interact and his predictions of soil depth.

 

These tables and graphs showed us that we needed to collect data from some moderate slopes (we had only very steep or flat), that some of our early samples did not have very good slope measurements because we were not using his new invention, and that we needed to find an area with a large obstacle and dig holes near medium obstacles both above and below it.

 

This process gives the last week of data collect some focus, so that even when we run out of time, we will have something tidy to present.

 

So 2 main things surprised me in the previous 2 weeks. First, ds really did not understand how you can take a scatter plot and draw line through it. In hindsight, I should have realized this might be a bit abstract. :rolleyes: It is actually a pretty tidy correlation: the greater the slope, the less soil there is. But when I drew a line through the middle of it, he did not understand why all the points of the scatter plot did not fall on the line. So we spent quite a bit of time hypothesizing what could have caused each point to fall above or below the line. Was it a moist area? above the line. Was is below a large obstacle? below the line. etc. Very interesting process to go through. I will need to reinforce his understanding of the graphing technique every week until it sticks.

 

The second thing that happened was that I had an epiphany as to the guiding principle for soil depth. Soil depth is fractal. (insert small pause while you think about that :blink: ) Fractal geometry is when equal patterns/variability repeat at every spatial scale (or time scale). Most people think of trees or shorelines as fractal. The variability in the land varies at all levels. In an area that from far away looks smooth, if you get close you see all the tiny obstacles causing pine needles to collect and causing more soil to build up below. As I said before there are big, medium, and small obstacles all affecting soil depth. Also, a large hill can face towards the sun but on this hill there will be small mounds that block the sun. Variability within variability. All of it interacts to affect the growth of plants and the collection of leaf litter, which in turn affect the depth of the topsoil!

 

So, how do you go about helping your children discover this idea for themselves? Slowly. The epiphany came to me in about 20 seconds, then I looked around for about 2 minutes to confirm it, then I spent 2 weeks slowly hinting and prompting my ds. The concept is not hard, and once he started to notice the variability on the spatial scales, I introduced the name. "Oh, that is called fractal geometry." Then, I started using the name all the time until it was as familiar as Tyrannosaurus Rex. Then, I brought up where else you might see it: smoke, clouds, lungs, etc. I knew that my ds really understood when he drew a tree. It was the best tree, by far, that he has ever drawn. When I commented on it, he said "well, I made it fractal." :lol:

 

Data collection: 2 hours

Write up: 5 hours

Discussion: 2 hours

Total time 9 hours over 2 weeks

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These are the reports that my ds reads when deciding if he will be going out. I just thought that some of you might enjoy seeing how variable weather is at this time of year!! Northerly to Southerly to Northerly to Southerly in a matter of 5 days. 45 knots is 52mph.

 

All he needs now are low wind Northerlies and Southerlies which he defined as 14 knots (16mph) or less. So I am not sure that we will be collecting any more data!

 

There are 2 maxims people say here. "No one moves here for the weather," and "If you don't like the weather, wait an hour."

 

 

Forecast: Gale warning.

Thursday: Northerly 15 knots rising to northwest 20 knots gusting 30 knots tonight. Slight sea becoming moderate tonight. Fine weather.

Friday: Northwest 20 knots gusting 30 knots turning southwest in the morning, then rising to 35 knots gusting 45 knots about the south coast in the afternoon. Moderate sea becoming rough in the afternoon but very rough about the south coast.

Saturday: Southwest 30 knots easing to 20 knots in the afternoon and to 10 knots at night. A few showers, clearing in the evening.

Sunday: Becoming northerly 10 knots in the morning, dying out at night. Becoming cloudy, a few showers developing.

Monday: Southerly rising to 15 knots. A few showers.

 

Swells: Southerly 2 metres, rising to 4 to 5 metres swells by Friday evening !!!!

Edited by lewelma
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Weeks 9 and 10. 6th grade

 

During week 9, we we able to get 2 more measurements. But it has gotten so cold now that he made the hard decision to skip the last 2 samples. So..... data collection is over!! :party:

After 3 more hours of cleaning up his notebook and documenting his work, his notebook now has the following pages:

1. Exploring ideas about sand

2. Brainstorming factors that affect sand movement

3. Exploratory data

4. Beaufort scale

5. Question

6. Methods: How data was collected

7. Experimental design

8. Diagram on how sand movement was measured

9. Problems and solutions

10- 13 Data collection

14 Data sorted by experimental design

 

Next is analysis! We spent 5 hours this week on thinking about what kind of graphs would describe his data and on making tables and graphs. This has been very difficult. There are a lot of variables. Independent variables: beach orientation, wind speed, wind direction. Dependent variables: sand direction and sand movement. I am trying very hard to advise only and not tell him what to do, but typically when a student learns to graph in math class, he is told what kind of graph to make and then handed the data. That kind of assignment is easy. It is NOT easy to figure it out by yourself.

 

He decides to make a scatter plot first. I remind him that the independent variable typically goes on the x axis. He graphs how wind speed affects sand movement in 4 situations: southerly on north-facing beach, northerly on north-facing beach, southerly on east-facing beach, and northerly on east facing beach. He shows me what he is planning and it looks fine. 45 minutes later he brings me the graphs to look at, and I realize that he has graphed wind speed from high to low. Hummm. I tell him that this is kind of confusing, and he agrees to re-graph all the data from low to high. When he brings me the redone graphs, I start studying them and realize that he has INVENTED data.:001_huh: I had not noticed this before!! He wanted his scatter plot to make a tidy correlation, so instead of plotting all the sand movements for a wind speed of 3, for example, he spread them out in the “best” way, plotting some at wind speeds of 3.1, 3.2, 3.3 etc. OK. Wow! Beaufort wind speeds only come in integers! I tell him the problem, and at first he is argumentative. “But, don't you remember, we often noticed that the wind speed increased while we were out there,” “I just put them in order,” etc. Then he was really frustrated “you want me to do it AGAIN?” Then he was mad “why didn't you see it before?” Finally, he was resigned and willing to listen. I did apologize for not noticing earlier, but told him that he truly is more likely to learn from this mistake than if I had told him what to do. This experience also reminded me about how much I know, and how little I can take for granted. My son is very good at math, but apparently graphing is a different thing.

 

The next day, I decide to be a bit more involved in the planning stage. So I suggest making some tables and a bunch of graphs and see what comes out. I figure that he could graph 10 different things and just keep the best 5. He is NOT interested in that approach. He says he knows what to do, but then he cannot draw me a sketch of his next graph. He says that he wants help, but then he won't take any advice.:banghead: I get up and get myself some chocolate! ;) When I come back, I decide on a different tact. I suggest that he ask a question about the data and then decide what kind of graph would best represent what he believes the data say. He looks at me blankly. So I remind him that when he started this project he knew nothing-- nothing at all. Now, he knows so much and simply cannot remember what it is like to be new to the topic. I suggest that he think about the protected nature of the different bays. He has definitely found that the east-facing bay is protected from Northerlies so sand movement does not vary regardless of wind speed; but in Southerlies the sand moves much more strongly in high wind. He has found something similar on the north-facing bay. So I suggest that he graph that. I ask him to sketch what a graph would look like that would answer this question. I wait. For a while. Finally, on his own, he comes up with 2 bar graphs, one for the protected wind direction for each bay and one for the unprotected direction. He finds that the sand movement is identical for the protected direction and very different for low wind vs high wind in the unprotected direction. These are beautiful graphs. Really nice.

 

The last graph he makes is pretty complicated. He did extra measurements on for high wind Northerlies on the north-facing bay because he was getting such odd results. And his graph was beautiful. If the wind is coming straight from the north, the sand moves hardly at all and in both directions along the beach. But if the wind is NW the sand moves strongly west and if it is NE the sand moves strongly east. Very tidy. The main problem he has is a lack of replication, so he will need to explain this graph.

 

So, this week definitely reminded me that scientists are trained, not born; and that scientific thinking is not natural. Even Mendel, the father of genetics, fudged his data. My ds is a very strong math student, has done 5 science fair projects before this one, has read lots of science books, watches lots of science documentaries, and comes from a science-oriented family. And he still is unable to determine how to display his data effectively, and he still struggles to remove his expectations from the reality of his data. My point is don't underestimate the need for training in scientific thinking and the scientific method. Learning the body of scientific knowledge is not enough.

 

Goals for next week: finish analysis, write up discussion, and begin working on poster. We have 3 weeks until the science fair.

 

Data collection: 3 hours

Documenting methods: 3 hours

tables and graphs: 5.5 hours

Total: 11.5 hours over 2 weeks

Edited by lewelma
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Week 11. 6th grade

 

Ok, it's crunch time.

 

We have continued with graph making for part 1 of his project (determining the correlation between weather and sand movement). Come June 1, we will be ready for Part 2: calculating the total directional movement of the sand in May at each beach. We worked for 45 minutes today to make up his schedule. He will need to darken and enlarge his graphs (by hand) for his poster because the originals need to be in his notebook. It is supposed to be a complete record of his project, and the poster is just a summary.

 

M pick photos, make last graph

T design methods for part 2, copy graph 1, print photos

W write the results for part 1, copy graph 2

H write discussion part 1, copy graph 3

F calculate part 2

 

M write results and discussion for part 2, label photos

T summarize methods and results for poster, copy table

W summarize intro and discussion for poster

H proof read, print

F glue everything to the poster

 

M design presentation

T, W, H practice presentation

F science fari!

 

Graphs 2 hours

Discussion and planning: 2 hours

Total time: 4 hours

 

 

Weeks 10 and 11. 2nd grader

 

I have not really been focusing on his project this week, but he has drawn up his fractal diagram and finished his last graph. Today we chose the photos and went out and took a few more. Tomorrow we will print them and make up a schedule for the next 2.5 weeks.

 

Graph and Diagram: 2 hours

Write up of methods and results: 1 hour (me typing)

Photos: 1 hour

Total time: 4 hours over 2 weeks

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  • 2 weeks later...

Weeks 12 and 13. 6th grade

 

So for the last 2 weeks, ds has been analyzing his data and writing up the results and discussion.

 

For part 1 (determining the correlation between weather and sand movement), we ran into a major problem with his very "beautiful" graph. To remind you

If the wind is coming straight from the north, the sand moves hardly at all and in both directions along the beach. But if the wind is NW the sand moves strongly west and if it is NE the sand moves strongly east. Very tidy.
We decide that he should show the wind and sand movement as arrows on a map of the area, so you can see the relationship. But what we find is that the coast does not face straight to the north, it faces NNE!! So his very tidy relationship now makes no sense.:confused1: Wind hitting the beach from the north should push the sand to the right because it is hitting the beach at an angle. Why in the world have we not looked at a map before? I have no idea.:001_huh:

 

After calming him down, I suggest that we verify his data, check that he calculated the averages correctly, check that he has graphed it correctly, look for outliers, etc. We find nothing. So now is the exciting part. Why did he find the unexpected? We start brainstorming. The most obvious reason that comes to mind is the effect of the tide. He controlled for tide and only collected data when the tide was coming in. We draw some pictures and hypothesize that the incoming tide is working counter to the wind direction and actually shifting the entire curve to the left (I know this probably makes no sense without the graphs, but I will post them next week when I have time.) It is very logical that the tide near an inlet is very important to longshore transport. He hypothesizes that tide will have little effect on the east facing bay because it would be perpendicular to the beach.

 

On June 1 he starts his calculations for part 2 (calculating the total directional movement of the sand in May at each beach). These calculations take some time because he needs to figure it out on his own. What he has to figure out is that the calculations will be a weighted average of how far the sand moves in each category (LS, LN, HS, HN: low wind southerly, low wind northerly, etc) based on how many half-days of weather he has in each category.

 

He starts with the raw data: the wind speed and direction for morning and eventing in May, and sand movement data. Ok, what does he need to do? These types of real life problems are really difficult for kids, even mathy kids like mine. So for me the real question is how to guide him through the thinking process without telling him the answer. My approach is to suggest general ideas. For example "most scientists start with tables, what kind of table would you need?" or "What kind of numbers do you need to put into a weighted average calculation? If you know what kind of numbers you need at the end this can guide you to figure out the first step in dealing with the raw data." There are a few key terms that I have to suggest to him, ideas like "half-days" or "extrapolating missing data."

 

I won't go through his whole thinking process, but just note some issues that came up. 1) He is missing one day of weather data, so I suggest to him that he extrapolates it from the day before and after. He baulks. "I can't do that. It's not allowed," so I get to tell him that it is allowed as long as he documents it in the text. 2) He gets confused and thinks that the weighted average is divided by 4 categories rather than 62 half days. 3) he needs to average NET directional movement, so he has to figure out how to deal with the beach where the sand moves in different directions depending on slight changes in northerly direction.

 

In the end, he figures it out, but it takes a while, and requires 2 additional tables. He finds that one beach is moving north and the other is not moving at all. Now, can we verify this? We look at google maps, and find that compared to the road which follows the coast, the sand has clearly accumulated on the north end of the beach, just where his calculates show it to! :hurray:Really really cool. He also wants to get a historical photo to verify his predictions further. He needs to approach the historical library and ask them to do research. I have refused to do it for him, but he is very squimish. He won't get it by the homeschool science fair, but perhaps by the regionals. We will see.

 

Finally, the write up. OH MY. The write up was incredibly difficult. This project expanded in scope over time, and because he is interested in the regional fair, he has to write the "full" version for his notebook and the summarized version for the poster. The full version is pretty easy. But because he a slow writer, I agree to type some of it while he dictates. The summary, however, is impossible. How do you summarize so much? I don't want to do it for him, so I let him stumble. Over and over again. We work together for hours, typing and retyping. Each taking turns at the computer. Trying this approach, trying that. I tell him it is iterative. Every time you write something, you learn more about how to shorten and explain better. As you can see below, writing and discussion take 28 hours over 2 weeks! In the end, I think he has it. I will post it for you to see.

 

To do next week: finish poster, finish notebook, design and practice presentation. Science Fair is on Friday!

 

Week 12

Graphing: 4 hours

Pick photos and develop them: 2 hours

Writing: 4 hours

Discussions: 4 hours

Calculations: 4 hours

Total: 18 hours

 

Week 13

Graphing: 2 hours

Writing and discussion: 20 hours

Layout: 2 hours

Making poster: 3 hours (not yet completed)

Total: 27 hours:001_huh:

Edited by lewelma
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6th grade: Text for ds's poster. 2 tables are missing because their formatting was difficult. Will post poster photos in a week when the posters are done.

 

Introduction

 

Beaches move over time. Shorelines evolve due to physical processes such as longshore transport. Longshore transport is the movement of sand parallel to the beach. It can destroy houses or roads that are too close to the beach by undercutting their foundations.

Longshore transport is mainly affected by the prevailing wind direction. Wellington has both Northerlies and Southerlies, and I predicted that beaches with different orientations to these prevailing winds would be acted on differently by longshore transport. I was also interested in using these relationships to predict the net direction of sand movement at my study sites.

PART 1

 

Questions: 1) How do wind speed and direction affect longshore transport? 2) How does the orientation of the bay affect this relationship?

 

 

Methods

 

Independent Variables

 

Bay Orientation – Selected 2 study sites with different orientations (Photos 1 and 2).

Wind Direction – Checked Metservice and verified locally.

Wind Speed – Checked Metservice and verified locally using the Beaufort scale. Classified as Low Wind or High Wind (Photos 3 and 4).

Tide – Controlled for tide by only taking samples during incoming tide.

 

Dependent Variables

 

Distance and Direction of Sand Movement – Took 3 measurements per visit and averaged them creating one data point (Photos 5 and 6).

 

Table 1: Experimental Design

................................ Number of samples obtained

wind direction/speed ...Worser.... Seatoun

Northerly Low Wind .......2........... 2

Northerly High wind ........4......... 4

Southerly Low wind ........4.......... 2

Southerly High wind .......2 ..........2

 

*Each sample included 3 measurements. Four additional samples were attempted but visibility was poor.

 

Photo 1: Seatoun Beach faces NNE. It is very exposed to Northerlies and protected from Southerlies.

Photo 2: Worser Bay Beach faces east. Northerlies and Southerlies run parallel to the beach.

Photo 5: I walked out 10m past the surf zone and emptied a container of sand on a ruler. This sand was a different color because it came from Oriental Parade beach.

Photo 6: I took an initial measurement of the spread of the sand, waited one minute and took a final measurement. The difference between them is the distance the sand moved.

Photo 3: Low Wind is 2 to 3 on the Beaufort scale (5 – 19 kph).

Photo 4: High Wind is 4 to 5 on the Beaufort scale (20 – 38 kph). High wind conditions required special collection procedures (see notebook for further information). It often took 45 minutes for a 30 second sample.

 

 

Results

 

The way wind speed and direction affects sand movement varies depending on whether the bays are exposed or protected from a specific wind direction.

 

Distance of Sand Movement

 

If a bay is exposed to a wind direction, like Worser in a Southerly, the higher the wind speed the further the sand moves. However if a bay is protected from a wind direction, like Worser in Northerly, then the amount the sand moves stays approximately the same (Graph 1).

 

Direction of Sand Movement

 

The direction sand moves varies depending on the direction a bay faces. Generally, sand moves the direction of the wind along the beach (Diagram 1).

 

Worser Bay Beach

On Worser when wind blows to the south (a Northerly), the sand moves south (and vice versa) because Worser is oriented north to south (faces east).

 

Seatoun Beach

On Seatoun this relationship is more complicated because the beach faces NNE. When wind blows to the north (a Southerly), the sand moves to the north along the beach which is WNW.

Northerlies hit Seatoun beach straight on, and small variations in wind direction yield a complete reversal of the direction of the sand movement (Graph 2). Unexpectedly, when the wind is perpendicular to the beach, the sand instead of moving in either direction, it moves strongly left along the beach.

 

 

Discussion

 

For the complex problem of High-Wind Northerlies on Seatoun beach, I approximated a curve to describe the distance and direction of Sand Movement, and found that the curve was shifted left along the beach (Graph 3).

I hypothesise that this is caused by the tide coming in and pushing the sand against the wind direction. To prove this hypothesis I would need to collect data when the tide is going out.

 

 

PART 2

 

 

3) Question: Are Seatoun and Worser Bay beaches moving?

 

Methods

Collected wind data in May. Classified each half-day into 4 wind categories (see Table 2). Calculated average sand movement at each beach for each wind category. Used a weighted average to calculate the net sand movement of each beach in May.

 

 

Results

 

Worser Bay beach is moving north three times faster than Seatoun beach (Table 3).

 

 

Discussion

 

My model excludes the effect of extremely high wind situations and the effect of outgoing tide.

 

Worser Bay Beach

Although Worser is not likely affected by tide, the net effect of high wind situations is that they likely make the beach move further north because Worser Bay beach is protected from high wind Northerlies but not high wind Southerlies. After completing this model, I checked Google maps and found that the road follows the beach closely except at the north end of Worser Bay beach, where sand appears to have accumulated (Photo 7).

 

Seatoun Beach

Although Seatoun is not affected by high wind situations, it is likely affected by tidal movement. Because I excluded outgoing tide, my results are likely skewed left along the beach (WNW) because ingoing tide likely pushes the sand left and outgoing tide likely pushes it in the opposite direction. Thus, Seatoun beach is likely not moving at all.

 

 

Conclusions

 

I have found that wind can be used to predict the amount and direction a beach moves through longshore transport. These relationships can be used to help city planners to place houses and roads in safe locations where the ocean will not undercut them.

Edited by lewelma
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