Lines of Symmetry

After sorting all the Board Games, the next task has been to declutter my Art Room and the Math & Science Room, where things tend to pile up.

I was extremely fortunate a few months ago to receive a very large donation of math curriculum materials from the estate of Dr. Ann Karmos. She held a PhD in Educational Psychology and she spent 33 years at SIU teaching Math Teacher Preparation in the Department of Curriculum and Instruction.

During my Spring Break I finally had time to sort through all of the bins. They are a treasure trove. Two things for Symmetry were totally new to me. One was Mirror Cards (I have both the inital 1965 trial edition that they sent to a few teachers to get feedback and the 1967 edition that was published and distributed more broadly). The child holds up a mirror at different angles and sees which designs can be replicated (have a line of symmetry) and which cannot. Very cool.

She also had a massive stash of wax paper sheets and at first I couldn't figure out why. We use them in Art, underneath our gelatin printing plates, but I didn't know why a math teacher would have them. Then I found an example.

Draw the design and then fold it to find the line of symmetry. Because it's wax paper you can see through it to the design on the other side. So clever!

Thank you to Ms. Marion for recommending our school for this donation. It's amazing. I will bring duplicate materials (including duplicate Mirror Cards, Cuisenaire rods, and more) to the April meeting of Homeschool Without Borders for anyone who would like them for their homeschool math stash.