Recommended resources for adding/subtracting positive and negative #s?

[happy2homeschool]

I'm looking for resources for teaching addition and subtracton of positive and negative numbers. We started these math concepts a few days ago and my son is not getting it -- which essentially means that I'm not explaining it well. Can you recommend any websites or worksheets or other resources?

Thanks,
Lori

[Carmen_and_Company]

Here's a site that works with integers: http://www.math-drills.com/integers.shtml and another that we've used, http://www.purplemath.com/modules/negative.htm

You may want to create a number liine that contains negative & positive numbers. Here are a few printable ones:
http://www.helpingwithmath.com/printables/others/lin0301number03a.htm

http://incompetech.com/graphpaper/numberline/


Here are pages with information on negative numbers:
http://www.mathsisfun.com/positive-negative-integers.html

http://www.eduplace.com/math/mathsteps/6/b/index.html

http://richardbowles.tripod.com/maths/posneg/pn.htm

http://www.cimt.plymouth.ac.uk/projects/mepres/book7/bk7i15/bk7_15i1.htm

[Jann in TX]

I usually teach this in terms of MONEY.

A positive number is how much you have and a negative number is how much you owe.

Everything is really ADDITION! ALL addition and subtraction problems have TWO signs between numbers! The 'rule' is that you can only have one sign (+ or -) between 2 numbers--so you hide the extra addition sign. You also do not write the sign in front of the first number if it is positive.
7+3 is really +7 + +3
7-4 is really +7 + -4

When you go to 'add' two numbers that have different signs the rule' is to subtract the smaller (absolute) value from the larger (absolute) value and then you keep the sign of the larger (absolute) value.
-14 + 8
subtract 8 from 14. The result is 6. Take the sign of the -14 since it's absolute value is the largest. Answer is -6.

Using MONEY I would explain it this way.
-14 + 8
You owe your teacher (me) 14 dollars. You have 8 in your pocket (and you give it to me). How much more do you need in order to pay me back in full?

Try to find some 'real life' examples to help with the understanding of the concept.

[5wolfcubs]

I taught it w/ a piece of paper w/ a tree drawn on it (years ago...I think so we could play a math card game -- but I'm pretty sure I got the idea on the internet). The "ground" was in the center of the paper, the tree went up, the roots went down. I then drew a vertical number line w/ 0 at the ground level. You either dug down or climbed up. And if you had dug 7' down and climbed up 10' (-7 + 10) where would you be? Underground still or in the tree? This made sense to all the kids.

[Sue G in PA]

My dd struggled with this, too. It just took time and lots of practice. I love the responses so far. I would also recommend the worksheets at www.mathusee.com Negative numbers is listed under the PreAlg. worksheet generator section, I think.

[happy2homeschool]

Thank you! :001_smile:
Thanks for these wonderful suggestions. I've printed out some of the worksheets to try this morning. I appreciate the explanations too -- this will help me explain the concepts and I think he'll be able to understand them now.

[gardenschooler]

I usually teach this in terms of MONEY.

A positive number is how much you have and a negative number is how much you owe.

Try to find some 'real life' examples to help with the understanding of the concept.

I try to relate as much as I can to money. It gets them paying attention. :D We had great success learning percents and fractions this way. Very motivating for young shoppers.

[happy2homeschool]

I printed out several worksheets from these websites and I explained the concepts using your suggestions and guess what happened -- my son understands this now! Thanks again everyone.:)

[summer]

I used Keys to Algebra..the first book. It was all negative numbers and adding and subtracting them.