## Thursday, September 24, 2009

### f(a bag of skittles)

Today, I realized mid-class my students desperately needed a review of working with functions to get through the limit definition of derivatives.  The picture below is what spontaneously occurred.  I wrote the left half and then had them tell me should be on the right.  They seemed to really enjoy it, and understood what was going on much better when we tried to apply it to the definition of derivatives.

f(x) = 5x + 1

1. I do the same thing in my class except I do smiley face, flowers, and the a number. It works out nicely in calc.

In trying to make things "real" in algebra classes, I think students are losing the idea that it's really just symbolic manipulation and what those symbols mean. In particular, I like this blog's entry on variables (maybe too conceptual for calc students, but I found it interesting):

http://sixwingedseraph.wordpress.com/2009/05/15/variables/

2. That'll do the trick. Nice.

3. wow, you just helped me! I've been frustrated as to why my alg 2 don't understand f(g(x))...Maybe this will help!

4. I'm a bit late, but... taping Skittles to the board in genius! I do the same sort of "scaffolding" and thought 'I' was creative.

5. This is so fun. I'm teaching Alg2 now! Miss you!! <3 Julie