Thursday, October 14, 2010

Sewing Math: Finding the Area of an Irregular Shape

R10 is working on transforming a little girl slipper pattern to an 18 inch doll slipper pattern. Her brother suggested finding the area of the shape and working from there...I believe we are working on "similar" shapes with this one.

So, we looked it up and decided the way to go was to divide the irregular shape into rectangles, squares and triangles and find the areas of those. So, she did and measured the sides. Then she got to practice:
  • changing mixed numbers into improper fractions
  • multiplying fractions
  • changing fractions into mixed numbers
  • reducing fractions
  • area of a rectangle
  • area of a triangle
  • dividing fractions
  • reciprocals
She got more than she bargained for, but she is still plugging away!

The Pattern- divided into common shapes and measured out


Our trusty Math on the Level manual for Geometry and Measurement- we reviewed the proper procedure here. I like the format of the quick reference for the teacher with MOTL.

Area of a triangle

I made this paper for her after showing her on scrap paper. I laid out the steps nicely so she could repeat it with each section. So much of what I am doing right now involves me quickly writing out an assignment for a child- not fancy but they are learning a TON!
learning to divide fractions by multiplying by the reciprocal


Sewing math is continuing to be a HUGE motivator for R10. More proof that using math instead of just doing math all the time is really effective. I'll have to update you when the smaller pattern is finished.

4 comments:

Kim Monaco said...

This is so awesome. I love the way that real math is being used and in a super practical way. My oldest really hates math, but sewing she could definitely get into. Time to change it up, I think.

Thanks for the inspiration!

Heather said...

You are welcome Kim!

Deb said...

That is fantastic! What a great story!

Courtny said...

Wow Thanks It Really Helped Me.. c(=