The first part of our next unit in math involves helping students derive the area and perimeter formulas for rectangles. Knowing what I know after doing this little “gig” for 20 something years, I was pretty confident that I needed to find out if, indeed, my students REALLY knew what a rectangle was. Simple right?

**False.**

I thought I’d start with asking students to jot down their thoughts about the following two questions:

As I walked around, I grew increasingly glad that I didn’t jump right into the first lesson of this unit! We had some foundations to build!

I brought us back together as a class and began showing the students some shapes that I had cut out of construction paper. One at a time, I held them up and we “played democracy”–majority ruled. The question? Is it a rectangle–or is it a “counterexample”. Here’s what we ended up with.

Sorry so blurry! Didn’t realize it at the time…and didn’t take a second shot! |

So…next steps? I asked the students to process the information they had learned in their notebooks. I asked them first to write about what they know to be true about rectangles, and then to make their own rectangle/not rectangle T-chart. We’ll see what they remember in a few days!