Seriously, we are starting to get into some pretty heavy duty thinking in the Teacher Studio! I wish I had a video camera to capture some of the amazing moments! I’m going to try to paint of picture of how things unfolded today. Sit back–I am still in awe over one of my mathematician’s understandings. Like–jaw dropping awe. . . and it takes a lot to impress me!

### Critiquing Reasoning and the Standards for Mathematical Practice

In a nutshell, the students needed to identify the shapes that were NOT divided into thirds, then pick 2 of them to defend–to “prove” they were not. This was a great start to the day . . . students were successful at this but–if you remember–I knew there were LOTS of misconceptions abounding in my room! So what I did next was hand out sheets of shapes that I had divided in different ways and sent the students off in groups to decide if “TRUE”–the shape WAS divided into equal parts or “FALSE”–the shape was NOT divided into equal parts. I gave the groups five minutes or so to decide and to come up with their arguments. Of the 6 groups, 4 came to consensus, 2 did not–so I told them the class would help them decide.