Davysmom Posted January 20, 2014 Share Posted January 20, 2014 My dd is struggling with negative numbers. No matter how I explain it, she is feeling frustrated! We have tears - lots of tears! I think she is just wanting to give up on this! Any good websites or ideas to explain this to her in a way that will help her understand? Quote Link to comment Share on other sites More sharing options...
Momling Posted January 20, 2014 Share Posted January 20, 2014 Sometimes kids just aren't ready for a topic and need time to really understand it. But... Negative numbers are usually taught in 6th/7th grade math, so if she's in Algebra 1, I wouldn't move on until she really gets it. She can't get very far without it. Besides lots of number lines, talk about elevators going down to basement 1, 2, and 3 rd floors, or feet below sea level, or how much money someone owes. It's easy to find real life examples for adding and subtracting negatives, but multiplying and dividing negatives is tricky to explain because it's so abstract. Key to Algebra book 1 is cheap and gentle and deals with negatives a bit. I'd probably start there. Quote Link to comment Share on other sites More sharing options...
lmrich Posted January 20, 2014 Share Posted January 20, 2014 The keys to series was super helpful. I have to run, sorry I cannot elaborate. Quote Link to comment Share on other sites More sharing options...
8filltheheart Posted January 20, 2014 Share Posted January 20, 2014 The way I teach it is by drawing a number line. So, say you draw a number line from 10 down to negative 10. If they add -3+ (-2), they should be able to see that is the same as moving down the number line from -3to -5. Now, if you start at the -5 and subtract the negative 2, that takes you back to the negative 3 which is the same as adding 2. If you have the negative 3 three times, that is (-3)(3) which is moving down the number line 3 time in a pattern of negative 3 equalling -9. However (-3)(-3) is moving the opposite direction of negative 3 three times, so it would be a positive direction equalling 9. Does that help? Quote Link to comment Share on other sites More sharing options...
wapiti Posted January 20, 2014 Share Posted January 20, 2014 I agree about spending a lot of time with the number line. I really like 8FilltheHeart's explanation of multiplying negative numbers. If she has a hard time with a horizontal number line, consider making a vertical number line (this is how I see numbers, myself). Tape a long strip on the wall. Simple real world examples to try: owing money debt and paying it back; outdoor thermometer. With these, use red pen/pencil for writing the negative numbers. I agree that this should be nailed down now before proceeding any further with algebra. Quote Link to comment Share on other sites More sharing options...
Erin Posted January 20, 2014 Share Posted January 20, 2014 it always comes back to money for us. ;) Negative numbers, you owe someone that much money. Positive means you have that much in the bank. If you're taking away, you're spending it. Already in debt? Well now you're *further* in debt. Already in the positive? Well now you're bringing that balance down. If you're adding, you're making money...etc, etc. Quote Link to comment Share on other sites More sharing options...
dereksurfs Posted January 20, 2014 Share Posted January 20, 2014 Khan Academy is great for this. My son used it for the same purpose and it really helped. Sometimes it helps to listen to another teacher's perspective on the same topic. I highly recommend Khan Academy for this type of supplemental instruction. Sal Khan covers many math topics in ways that are very clear and understandable: https://www.khanacademy.org/math/arithmetic/absolute-value/add-sub-negatives/v/negative-numbers-introduction Quote Link to comment Share on other sites More sharing options...
albeto. Posted January 20, 2014 Share Posted January 20, 2014 There might be a topic of interest for her that applies this concept in "real life," in such a way that the lessons can't. For my son it was Star Trek - matter / anti-matter. ;) Quote Link to comment Share on other sites More sharing options...
MomatHWTK Posted January 20, 2014 Share Posted January 20, 2014 Here's another recent thread on the topic: http://forums.welltrainedmind.com/topic/499526-subtracting-a-negative-multiplying-2-negatives-explanation-help-please/?hl=%2Bnegative+%2Bnumbers&do=findComment&comment=5395738 Quote Link to comment Share on other sites More sharing options...
SilverMoon Posted January 20, 2014 Share Posted January 20, 2014 We do horizontal number lines on the big whiteboard. Works like a charm. Quote Link to comment Share on other sites More sharing options...
AngieW in Texas Posted January 21, 2014 Share Posted January 21, 2014 It looks young, but Cyberchase is really great for this. There was a wonderful episode for negative numbers that is shown in 3 parts on youtube. Quote Link to comment Share on other sites More sharing options...
texasmama Posted January 21, 2014 Share Posted January 21, 2014 The keys to series was super helpful. I have to run, sorry I cannot elaborate.We used Keys to, as well. Quote Link to comment Share on other sites More sharing options...
Davysmom Posted January 21, 2014 Author Share Posted January 21, 2014 Thanks! We have done lots of number lines and money. She completely understands that until they throw it into an long algebra problem. She never struggled with them before this. The problems are longer and more complex than working a number line or dealing with money. I am not sure what the issue is. She got every problem with more with one set of negatives wrong. Keys - looks great. I will check that out. Never heard of that before. We found a helpful video at Khan - thank you! I always forget to check there. That was very helpful! It sparked some good conversations today. I took it from math to English. She is a grammar and language student. (She studies 3 languages.) I told her math was just another language. And I put negatives into grammar terms. She did much better today. Thanks! Quote Link to comment Share on other sites More sharing options...
dereksurfs Posted January 21, 2014 Share Posted January 21, 2014 Thanks! We have done lots of number lines and money. She completely understands that until they throw it into an long algebra problem. She never struggled with them before this. The problems are longer and more complex than working a number line or dealing with money. I am not sure what the issue is. She got every problem with more with one set of negatives wrong. Keys - looks great. I will check that out. Never heard of that before. We found a helpful video at Khan - thank you! I always forget to check there. That was very helpful! It sparked some good conversations today. I took it from math to English. She is a grammar and language student. (She studies 3 languages.) I told her math was just another language. And I put negatives into grammar terms. She did much better today. Thanks! Glad to hear it. Khan approaches things from so many levels it is really great for targeting specific areas like this. We've used it for algebra as well as elementary math for this very reason. And yes, graphing algebraic expressions with negative numbers can throw kids for a loop. There's just a lot to take in. Its pretty normal to spend more time here looking at it from different angles. In fact I encourage you to slow it down a bit to practice and think through more examples. This is one of the more challenging areas of Algebra 1. ;) Quote Link to comment Share on other sites More sharing options...
Davysmom Posted January 21, 2014 Author Share Posted January 21, 2014 Glad to hear it. Khan approaches things from so many levels it is really great for targeting specific areas like this. We've used it for algebra as well as elementary math for this very reason. And yes, graphing algebraic expressions with negative numbers can throw kids for a loop. There's just a lot to take in. Its pretty normal to spend more time here looking at it from different angles. In fact I encourage you to slow it down a bit to practice and think through more examples. This is one of the more challenging areas of Algebra 1. ;) I think slowing it down will help. She is not used to slowing things down - she is used to just moving through it. I think she wants to just skip through this. LOL! I haven't been a lot of help because Algebra wasn't hard for me, and I couldn't find new angles to look at it from. We appreciate the help. Quote Link to comment Share on other sites More sharing options...
Wendy Inman Posted January 21, 2014 Share Posted January 21, 2014 I agree that the major thing that worked for us was slowing down. Just staying on that topic until he got it, no pressure to move on. We used Khan videos/practice and extra drill sheets downloaded somewhere off the web. :) Quote Link to comment Share on other sites More sharing options...
dereksurfs Posted January 22, 2014 Share Posted January 22, 2014 I agree that the major thing that worked for us was slowing down. Just staying on that topic until he got it, no pressure to move on. We used Khan videos/practice and extra drill sheets downloaded somewhere off the web. :) Yes, Wendy. We found this especially true for the Graphing Linear Equations chapter of TabletClass which I see you are using. That was a very challenging chapter. Quote Link to comment Share on other sites More sharing options...
Erin Posted January 22, 2014 Share Posted January 22, 2014 She never struggled with them before this. The problems are longer and more complex than working a number line or dealing with money. I am not sure what the issue is. She got every problem with more with one set of negatives wrong. Ah. I wonder if she's having trouble with that oh-so important concept; there is no such thing as subtraction in math. Even in the 1st grade when you did 3-2=, you were actually doing 3+ -2= At our house, we ALWAYS change subtraction to "add the opposite." I've noticed Buck is much less likely to miss a change in positive/negative when we start out changing the subtraction symbol. Quote Link to comment Share on other sites More sharing options...
Davysmom Posted January 22, 2014 Author Share Posted January 22, 2014 Ah. I wonder if she's having trouble with that oh-so important concept; there is no such thing as subtraction in math. Even in the 1st grade when you did 3-2=, you were actually doing 3+ -2= At our house, we ALWAYS change subtraction to "add the opposite." I've noticed Buck is much less likely to miss a change in positive/negative when we start out changing the subtraction symbol. This is very helpful. I bet you are right! Today was much better! Quote Link to comment Share on other sites More sharing options...
texasmama Posted January 22, 2014 Share Posted January 22, 2014 We park on concepts using material other than our main ones, as well. Currently, we are taking an AoPS break in Chapter 5 of pre-A to practice the concepts with Keys to Algebra (book 3) and Zaccaro Real World Algebra. Then we will hit AoPS again and see if the concepts are more clear. Quote Link to comment Share on other sites More sharing options...
Haiku Posted January 22, 2014 Share Posted January 22, 2014 If you can get a copy of Dolciani Pre-Algebra, it teaches how to work with negative numbers very well. Quote Link to comment Share on other sites More sharing options...
deanna1949 Posted January 24, 2014 Share Posted January 24, 2014 Have you tried algebra tiles? I just ordered them, so I have no firsthand experience. Each side is a different color, one is positive and one is negative. http://www.amazon.com/Working-Algebra-Tiles-Grades-6-12/dp/1583242171/ref=sr_1_5?ie=UTF8&qid=1390607408&sr=8-5&keywords=Algebra+tile Quote Link to comment Share on other sites More sharing options...
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