Monday, September 13, 2010

Math, Shapes and more Shapes

I mentioned earlier in the week that Selena had learned how to take a rectangle and make it into a square, then by folding the paper again made a triangle. I thought it would be fun to expand on this new found skill.

We started out with the rectangle and I asked Selena to make a square, then we unfolded it and I asked her how many squares make a rectangle? We used her pattern blocks to help her understand this concept easier.

100_3493 I then asked her to refold the paper and make a triangle out of it. Again we unfolded the paper and I asked her how many triangles were made from the rectangle?

100_3495She quickly placed four triangles on her piece of paper, so we counted one rectangle, two squares and four triangles.

100_3497 We found a diamond shaped pattern block, and it didn’t take Selena long to figure it would take two triangles to make a diamond.

I then took the hexagon, and asked her how many triangles it would take to make this shape. She struggled a bit with this one, so I got her started, basically just showing her how to place two triangles to begin her pattern, she then finished and determined it would take six.


We continued on with the trapezoid shape. Selena was beginning to get tired of this, but I urged she at least try to finish this one. Again I asked her how many triangles it would take to make her trapezoid.

100_3499 She got two on there, and quit, I asked her if she could fit one more on it. She looked and examined it for a minute and decided that she could indeed get one more triangle on the trapezoid. Though they moved around a bit under her little fingers, she did observe that she could fit three triangles on this one trapezoid.


Selena had fun trying to guess the amount of triangles she would need, then trying to see if she had guessed right. I know this will be a definite exercise we will do as often as she will work with it. I personally was never great with geometry, so it is my hope that by starting young, Selena will be better in geometry then I was.

I am linking this up at Joyful Learner, come and see what other families are doing in math.

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  1. I never really liked geometry that much either. I didn't like proofs. I liked algebra better. Good activity.

  2. We are going to be working with squares this week, too! Fun and valuable learning for Selena!

  3. Great exercise. I like using simple shapes to build more complex shapes. You might want to read "The Greedy Triangle" - it plays with this idea.

  4. Great idea, and very clever girl! I have a quilt design set that is full of little triangles in all different colors. I should dig it out and see if it helps my son with that lesson - he definitely doesn't know about splitting a rectangle into two squares, square into two triangles, etc. yet. And I'm pretty sure he has never heard of a trapezoid. (Fancier shapes are on my list of things to teach). :)

  5. I remember math problems on the SAT that dealt with figuring out area which involved being able to break apart shapes. I had intended on teaching her this concept when JC was older but I guess you can start young as long as it's a game for the child. I love how it began as a natural discovery from Selena!