One activity within the quadrilaterals lab was to fill in a hierarchy of quadrilaterals based on their properties. The learners were using shape makers and I thought that they would have a general understanding of how a hierarchy worked. After a while of them making conjectures but leaving the hierarchy blank, I decided to ask a few questions. From that formative assessment I was able to see that they really didn’t understand how the hierarchy worked. As a class, they pulled their chairs up to the whiteboard and we discussed certain aspects of the hierarchy- most specific, least specific, which way the arrows should point, etc. Looking back, I wish we would have discussed a general case before even introducing the hierarchy. This way I could ensure the learners knew what they were supposed to do before going into it. I included a page from Shape Makers text that discusses this. Going forward that is definitely something I am going to do. Further, as learners began to investigate specific quadrilaterals in their groups and develop proofs, I noticed that the kite group and trapezoid group were thinking about inclusive and exclusive definitions without realizing they were. Since their textbook shows the properties of a trapezoid have exactly one pair of parallel lines and the shape makers activity is based on having at least one pair of parallel lines, I knew it was a conversation worth having. So, the third day, before presentations, we had a brief discussion on inclusive and exclusive definitions, what changes when you use one or the other, and the benefits and drawbacks of each. Then I gave the students five minutes to fix any errors on their posters (notice the just kidding label on the kite poster). I included the page on trapezoids from Shape Makers because I used in the brief discussion. If I hadn't been walking around and communicating with groups I could have left a lot of learners confused. Go formative assessment!