Skip to main content


7th Grade Math - Area and Perimeter

Clip 6/11: Problem 2 - Area & Perimeter Part A


In this section, Patty and I begin to move students to the core mathematics of the Pizza Crust problem by looking at the relationship between area and perimeter.

Teacher Commentary

Here, our goal was to focus on justification, connecting what we had done in the previous problem to problem two; we strategically chose student work that could elicit this. We wanted to reinforce that idea of proof by asking the students "Where does the 36 square units come from?" Little did we realize that our focus would become language-based. The idea of "square units" and "inches squared" came up, and we had not anticipated this coming up in our planning. We had to address that within the lesson, as well as the idea of "crust" and "edge."

So while we intended to focus on justification, we had to address language. This meant a discussion with the class on the terms "inches squared," or what we meant when we say "around the edge." With populations of English language learners like this classroom, developing that academic language became an important part that we needed to address before we could even get to justification.