We are still working on this activity from Mathalicious.com and we are starting to discuss how to go "backwards" (find the square root). So I ask them to count out 90 beans with their table mates. Just this part of the activity had great conversations happening between students.
"Count out piles of ten."
My response: "Why do you want to count out piles of ten?"
"Because it's faster to count Miss Sadie!" <–a DUH look in my direction
"This doesn't even LOOK LIKE 90"
My response: "How much does it look like? Why don't you think it looks like 90?"
"Like 25. Because the beans are small."
We move on to the real question of the activity: "Can you make a square using 90 beans?"
Lots of moving around, counting out, I even had a student use the perfect square strategy we recently discussed in this lesson (2n+1, can you find the picture of this one?)
However, there was only one group that figured it out. The bell rang before our discussion BUT we are making great movement towards multiplying polynomials.