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Okay, this may seem like a dumb thing to ask about, but I'm having the hardest time getting my 13 y/o to make a hypothesis with his science experiements.  He doesn't want to "guess".  I've tried explaining the whole thing to him and nothing I say convinces him that he just needs to guess what will happen.  He wants to have all the details and basically KNOW what is going to happen.  He keeps just leaving the hypothesis blank on all his lab reports.  Any ideas for how to explain to him the purpose of the hypothesis and get him to actually take a guess?

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Remind him that he already has several years' experience in how the world works, plus he has already learned much in previous science studies, so he is not just "guessing." He using an existing basis, identifying how it all might fit together. You might want to ask leading questions about the new situation to give him a foundation for comparing it to prior experiences. Would that help?

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I do not agree that any science lab must begin with a hypothesis. Much great science arose from "just wanting to see" without preconceived notion.

You do not need a hypothesis. You need a question. What are you trying to find out?

 

For example, if I have a pendulum (a mass at the end of a string), I could simply want to find out whether the period depends on the amplitude or not, or on the mass or not, or on the length of the string - and that can be my objective: find out IF, and maybe in which way. I do not need to have a "guess" of the answer beforehand; that is highly artificial. All I need to have is a question.

 

I have a PhD in physics and did research. I have never begun any investigation with a "hypothesis". I had a question, and was looking for an answer.

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You could present it in terms of any scientific process that he is familiar with, where he can identify the process involved to arrive at an outcome.

The process can be seen as a series of variables, to arrive at the outcome.

But what if we change one of the variables?  

How will it effect the outcome?

We can make a guess about how it will effect the outcome, which is our hypothesis.

Which we then need to test, to see whether our hypothesis is correct or not?

Then write a report on the results.

While our hypothesis might not turn out to be correct?  It is often through this process that unexpected discoveries are made.

 

Though it needs to be presented as an educated guess, where he analyses the details of the variable, to arrive at an informed guess as his hypothesis.

 

 

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I sometimes use this cross-disciplinary chart.

http://www.readingquest.org/pdf/crossdisc.pdf

 

I use: hypothesis/question/problem/goal. and keep it pretty open ended. Having any type of goal or question or statement is enough.

 

Much science does not fit into many of the rigid and overly simplistic generic lab worksheets. All science doesn't have hypothesis and variables, and even when it does, that is often during a later cycle of investigation. A lot of time is wasted by assigning variables too early or at all.

 

I also often assign a little research before the student writes their hypothesis/problem/question/goal. I expect the student to be able tell me how their goal is based on their research, or I send them back to do more research.

 

I do sometimes assign a variable based experiment. Mr Q has some decent ones. But I use them rarely and they are not the standard template for what we usually do. Here are some Mr Q generic lab sheets that are not easily found on his site. http://www.eequalsmcq.com/sciencewise.htm. The instructions are free in the free life science text. http://www.eequalsmcq.com/ClassicScienceLife.htm

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I think Regentrude has a great point.

 

Do you want him to learn scientific thinking, lab skills, spark his curiosity, etc.?

 

Or do you want to follow the procedure as outlined in your curriculum to the letter?

 

If it's the former then let go of the hypothesis and just let him ask a question.

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Agreeing with PPs. As another scientist coming in here, I have somewhat of a problem with how the "hypothesis" has been given so much weight in modern science classrooms and K-12 teaching. I think it creates a barrier and implies that is how science is really done, when it isn't. What I have seen in practice, and what I am encouraging for my kids, is questions like, "let's see if..." or "what happens when I..." or "Oh huh, that's different...". Often, it really does start with paying attention and making observations.

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It's funny because I've just been reading Zen and the Art of Motorcycle Maintenance. He describes using the scientific process to solve a mechanical problem in the motorcycle. He constructs a question that does not rely on any information you don't already have: "What is wrong with the cycle?" Well, you've got a strong hunch it's electrical. So your first hypothesis is, "The trouble is in the electrical system." Then you design the experiment to verify whether or not that is where the problem is. You carefully test the spark plugs, which don't fire, verifying the hypothesis. Now you can ask a new question. "What is wrong with the electrical system?" You've got to have an *idea* to springboard from. In fact, if you really thinks you can consider a million ideas, some sillier than others. The one that's worth testing, that's the one that becomes the new hypothesis.

 

So for regentrude's example I'd say, the question is "Is there a recognizable pattern to the pendulum's swing?" and the hypothesis is, "I suspect there is a relationship between the period and amplitude." That way you know what to test and measure, you know? If you have NO guesses you're shooting blind, shotgunning around and not solving anything.

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The reason for the hypothesis is to be able to step from "general observations" to ONE answer that is ONLY a yes, a no, or math.

 

It's not about "guessing" (and hoping to be right) at all. It's about providing something highly specific: to prove or disprove -- both proving and disproving are good things. General discovery experiments do not make that leap.

 

Try asking for the hypothesis like as if it were a debate team resolution (if that's familiar at all). "This experiment will clearly substantiate that the following sentence is EITHER true or false: That bubbles rise at different speeds in various liquids." -- if different speeds are recorded, the hypothetical statement is proven true, if not, it is proven false. All other observations are extraneous idea starters, or are available for analysis that goes beyond the hypothesis that the experiment was "checking out".

 

A hypothesis is never 'a wrong guess' -- it's just there to go either way, based on the results.

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The reason for the hypothesis is to be able to step from "general observations" to ONE answer that is ONLY a yes, a no, or math.

 

It's not about "guessing" (and hoping to be right) at all. It's about providing something highly specific: to prove or disprove -- both proving and disproving are good things. General discovery experiments do not make that leap.

 

Try asking for the hypothesis like as if it were a debate team resolution (if that's familiar at all). "This experiment will clearly substantiate that the following sentence is EITHER true or false: That bubbles rise at different speeds in various liquids." -- if different speeds are recorded, the hypothetical statement is proven true, if not, it is proven false. All other observations are extraneous idea starters, or are available for analysis that goes beyond the hypothesis that the experiment was "checking out".

 

A hypothesis is never 'a wrong guess' -- it's just there to go either way, based on the results.

 

But that gives students a false impression of how research scientists actually work.

Most questions they investigate do not have one single yes or no answer.

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But that gives students a false impression of how research scientists actually work.

Most questions they investigate do not have one single yes or no answer.

Really? I was always under the impression that was the standard for 'proving things' experiments... I guess there are a lot more 'just exploring things' experiments going on than I was led to believe? Or are there branches that are more open ended vs branches that do things with specificity?
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And yet another scientist chiming in here. 

 

I agree with the others who said that real scientists don't do hypotheses the way K-12 science programs seem to think they do.  And a hypothesis is most emphatically *not* a guess.  Your son is right to resist.

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Really? I was always under the impression that was the standard for 'proving things' experiments... I guess there are a lot more 'just exploring things' experiments going on than I was led to believe? Or are there branches that are more open ended vs branches that do things with specificity?

 

Very often, the experiment is first and a theory for it is developed later, sometimes much later.

For example, superconductivity has accidentally been discovered early in the 20th century and a theory for understanding superconductivity was not developed until 1957.

ETA: Einstein did not predict the photoelectic effect in his 1905 paper and then had other scientists go look for it- he explained an experimental observation that had been made as early as 1887.

 

Most research in condensed matter physics has experimentalists exploring, and theorists explain afterwards (after which then more experiments are performed to see if predictions come true).

The discovery of the Higgs boson that had been predicted by theory decades ago and that has been looked for very specifically is NOT typical. High energy physics is expensive and you would not build such an extremely expensive machine unless you had a very specific objective. But in condensed matter physics scientists are "just exploring" all the time.

 

 

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So, I get that in the context of theoretical physics. It makes a lot of sense, and I'm getting the impression of the place of wide exploratory experimentation.

 

You also mentioned a second stage of "seeing if the predictions come true" -- which, I imagine, involves hypotheses?

 

I also wonder if, perhaps, there might be other sciences that have more to do with proving/disproving hypotheses? More concrete sorts of fields of research with more limited scopes than advanced physics? (Like medical research, or crash-testing vehicles, or creating hybrid plants, or developing chemicals for specific desired characteristics?)

 

Am I right in guessing science is done in both these ways, and it's wrong to only do it one way in school? Or are you saying that all science is now being done without proposing a prediction to test?

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Am I right in guessing science is done in both these ways, and it's wrong to only do it one way in school? Or are you saying that all science is now being done without proposing a prediction to test?

 

Yes, science is done both ways, and presenting it the way school does is extremely narrow and discourages free exploration.

And of course there is also very specific testing of hypotheses: if a theory predicts xyz will happen, experiments are then done with the hypothesis "xyz will happen (or will not happen)" . But that's not all of science.

 

The first thing is always to observe something in nature, either by accident, or by messing around with stuff to "see what happens".

Then you start thinking about why that is so, and THEN you come up with one or several competing hypotheses, and those you can then test in a targeted manner. All of the above steps can be taken by one person, or may be divided among many different people.

Once a theory predicts "xyz will happen", experimentalists may start varying scenarios, looking at different systems, and seeing if the prediction still comes true.

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The first thing is always to observe something in nature, either by accident, or by messing around with stuff to "see what happens".

Then you start thinking about why that is so, and THEN you come up with one or several competing hypotheses, and those you can then test in a targeted manner. All of the above steps can be taken by one person, or may be divided among many different people.

Once a theory predicts "xyz will happen", experimentalists may start varying scenarios, looking at different systems, and seeing if the prediction still comes true.

 

 

Yes.  I'm in the earth sciences.  For us it is often impossible to make a prediction and then test it directly...let's see if I can make a glacier and then set it loose for a couple thousand years and see if it makes a valley like this.  Or make a shield volcano erupt enough to turn into an island.  Or intentionally release a plume of solvents into an aquifer to see how far it travels.   I could give a million examples that aren't going to happen.  So instead, there is a LOT of observation, comparing different types of situations with different types of ongoing processes.  After that, you may have enough understanding to make some general predictions, which are then refined by experiments or modeling. 

 

And IMO that's one big reason why the earth sciences are often given the short shrift in K-12 and science fairs...the way it is done just doesn't fit into the "hypothesis/scientific method" model emphasized or prescribed in those situations.  But that's a rant for another day and probably not very helpful to the OP.  :D

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  So instead, there is a LOT of observation, comparing different types of situations with different types of ongoing processes.  After that, you may have enough understanding to make some general predictions, which are then refined by experiments or modeling. 

 

And IMO that's one big reason why the earth sciences are often given the short shrift in K-12 and science fairs...the way it is done just doesn't fit into the "hypothesis/scientific method" model emphasized or prescribed in those situations.

 

And the bolded is what I miss in science education: observing with an open mind and encouraging students to first observe and notice and then ask why and how questions - for which they may not have a clear-cut yes/no answer they can test in a pre-packed "lab".

Science is NOT all cut-and-dried fitting neatly into the boxes of a "lab report" template. Science is first notebooks full of observations and ideas, of which a tiny fraction will lead to a great new theory.

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Wow, thanks for all the thoughts!  I feel a little in over my head here as I am more of a history geek than science geek....

 

So, I do have another question... I think some of you touched on this....

 

So, the experiments pretty much are designed to lead you to one outcome.  There doesn't seem to be a lot of "mystery" involved.   A lot of the time it doesn't take a brain surgeon to figure out what is going to happen in the experiment.  Put baking soda and vinegar together and of course you're going to get bubbles.  (very simplistic to serve a point) 

 

In "real" life I would think a scientist would start with a problem and experiment to find the possible answers.  It seems like in all the experiments we do the problem is staged and a "correct" answer is to be found (which leads to the experiment either succeeding or failing based on the expected outcome the author of the text wants).  To me, the untrained science mom, there seems to be very little mystery invovled.  Maybe that's where learning the process starts?

 

I don't know if I'm making any sense at all?  I love the content of our text (Apologia), but I really struggle with the experiment part.  I'm not quite sure what the goal in doing the projects is.

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And the bolded is what I miss in science education: observing with an open mind and encouraging students to first observe and notice and then ask why and how questions - for which they may not have a clear-cut yes/no answer they can test in a pre-packed "lab".

Science is NOT all cut-and-dried fitting neatly into the boxes of a "lab report" template. Science is first notebooks full of observations and ideas, of which a tiny fraction will lead to a great new theory.

 

I think this gets at my post above........

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Regentrude, you have done a great job clarifying things, and I completely agree.

 

In my research in population ecology, I wanted to know *how* weather affected population size and with what time lag.  The goal was to build a statistical model that would explain 25 years of data.  The building of the model took 3 years of full time research.  I'm not even sure what the hypothesis would have been.  I uncovered a lot of interesting relationships, but did not prove any preconceived ideas. 

 

Hypotheses are often important in *experimental* science, but that is only one way to answer questions.  How, exactly, would I have changed the weather to see if a hypothesis was correct?

 

Another use of the word 'hypothesis' would be for use in statistical analysis.  You need a null hypothesis so you know exactly what you are trying to disprove. But I assume this is not what your son was asked to provide.

 

I often find that in the effort to make demonstrations appear to be experiments, kids are asked to dress the demo up in the language of science.  But all this does in my experience is confuse the students.  The best way for a student to learn about creating hypotheses would be to observe something for a few weeks, and then ask a question that was interesting to him.  Then, if the question could be answered with an experiment (rather than observation or model building etc), to come up with an informed opinion as to the outcome, which is a hypothesis.  In contrast, what your ds has been asked to do is very artificial.

 

Ruth in NZ

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This is why I had my children do two years of natural history and then take science at the community college. The first two years of science they WERE scientists - they learned to made observations and to design experiments, real experiments, ones where they had no idea what was going to happen, and they learned to record both. Then they learned to take science classes and filled in some of the essential scientific knowledge at the community college.

 

Robyn - I haven't seen Apologia, so ignore this if it doesn't make sense, ok? I think you need to tell your student that this is a CLASS. It is meant to teach someone basic scientific knowledge, knowledge that has already been discovered and the experience of the scientific community tells us is true. The "experiments" in the course are not really experiments - they are demonstrations. They serve two purposes: they give a hands-on demonstration to help the student to understand certain concepts, and they teach the student how to document an experiment. The two should not be mixed together, but in an effort to be efficient, they are. Tell him the whole process is very contrived and inaccurate and just to play along and make the guess he thinks the course wants him to make, even though he obviously wouldn't have the expertise to make it in real life. Tell him that in a real situation, the whole thing would make more sense because by the time he got to making that "guess", it wouldn't really be a guess but a question of I-think-it-works-like-this-so-I-am-going-to-try-it. Explain the null hypothesis (where you deliberately make a statement you think is wrong and try to prove it in order to disprove it). And explain that before he got to that point, he would have done many "experiments" where the purpose was exploritory and/or to make observations, not to prove or disprove a hypothesis. If you want, you can teach him how to keep a scientific notebook and how to write up a real experiment, one which doesn't necessarily have a hypothesis. (My husband has to "prove" things all the time for businesses and the government and works with things that are "provable" in a lab (unlike much of natural history or geology) and even he said that many of his experiments are simply exploratory. That doesn't mean they aren't recorded, though, and he gave us the format he uses for that and worked with my youngest to teach him to design and write up an experiment properly and keep a lab notebook. I can send you the format, if it would be helpful. It is pretty standard. It just emphasizes purpose rather than hypothesis. The purpose is often "exploratory". It is fairly easy to find directions for keeping a lab notebook on the web.)

 

HTH

Nan

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This is why I had my children do two years of natural history and then take science at the community college. The first two years of science they WERE scientists - they learned to made observations and to design experiments, real experiments, ones where they had no idea what was going to happen, and they learned to record both. Then they learned to take science classes and filled in some of the essential scientific knowledge at the community college.

 

Robyn - I haven't seen Apologia, so ignore this if it doesn't make sense, ok? I think you need to tell your student that this is a CLASS. It is meant to teach someone basic scientific knowledge, knowledge that has already been discovered and the experience of the scientific community tells us is true. The "experiments" in the course are not really experiments - they are demonstrations. They serve two purposes: they give a hands-on demonstration to help the student to understand certain concepts, and they teach the student how to document an experiment. The two should not be mixed together, but in an effort to be efficient, they are. Tell him the whole process is very contrived and inaccurate and just to play along and make the guess he thinks the course wants him to make, even though he obviously wouldn't have the expertise to make it in real life. Tell him that in a real situation, the whole thing would make more sense because by the time he got to making that "guess", it wouldn't really be a guess but a question of I-think-it-works-like-this-so-I-am-going-to-try-it. Explain the null hypothesis (where you deliberately make a statement you think is wrong and try to prove it in order to disprove it). And explain that before he got to that point, he would have done many "experiments" where the purpose was exploritory and/or to make observations, not to prove or disprove a hypothesis. If you want, you can teach him how to keep a scientific notebook and how to write up a real experiment, one which doesn't necessarily have a hypothesis. (My husband has to "prove" things all the time for businesses and the government and works with things that are "provable" in a lab (unlike much of natural history or geology) and even he said that many of his experiments are simply exploratory. That doesn't mean they aren't recorded, though, and he gave us the format he uses for that and worked with my youngest to teach him to design and write up an experiment properly and keep a lab notebook. I can send you the format, if it would be helpful. It is pretty standard. It just emphasizes purpose rather than hypothesis. The purpose is often "exploratory". It is fairly easy to find directions for keeping a lab notebook on the web.)

 

HTH

Nan

 

This is helpful!  Thank you Nan!  I think this is what I've been trying to figure out.  I will explore the idea of a science notebook... I like your explanation of the "experiment".  I think this will make sense to my boy!  He's a smart one... he keeps me on my toes! I like the idea of "purpose" rather than hypothesis....

 

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The smart ones see right through misleading or incomplete or inconsistent teaching. Or behavior lol. They keep us honest. My children quickly taught me to give them the real reason for something. The fake reasons didn't hold up. They were realists and willing to do a certain amount of playing along and jumping through hoops to achieve a purpose, but woe betide the person who wasn't honest about what exactly that purpose was. They refused to play if I told them the reason for finish a bad textbook was to gain knowledge when it was really to finish a imperfect-but-convenient textbook so that they could get into engineering school. They were perfectly capable of understanding that they didn't have enough background knowledge to understand something, but they refused to play if I pretended that a textbook was all true if it glossed over or left out the bits which were too complicated for them to understand early on in their education. We did much better with college level for-non-majors textbooks. They may not have understood everything, but at least the books didn't oversimplify to the point where things like the explanation for genetics didn't make sense. And as you can tell, I found the whole process pretty frustrating grin. The genetics incident happened over ten years ago and I am STILL talking about it. I would rather have children who were inconveniently clear-sighted than blind followers, though, so all is well. : )

Nan

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 We did much better with college level for-non-majors textbooks. They may not have understood everything, but at least the books didn't oversimplify to the point where things like the explanation for genetics didn't make sense.

 

Yes! When my kids were still in public school, I found so many errors in their science textbooks!

It is indeed very difficult to explain certain things to children, but a simplification should never lead to something incorrect.

 

We have discussed this on these boards elsewhere: school books are adopted by people without subject expertise, whereas college texts are adopted by professors who themselves are experts in the subject for which they choose the book. That explains a large extent of the quality difference.

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