In my previous post: https://mathmindsblog.wordpress.com/2014/11/26/always-sometimes-never-year-2/ the class organized the quadrilateral cards into A/S/N columns and today we continued that work.
I switched the groups up so I had students entering a new set of cards with differing views. Always fun stuff for some great mathematical arguments. I had them discuss differences they saw from their previous table and decide if they want to move any cards.
Having each group do a written proof for all 18 cards seemed overwhelming, so I gave each table 3 of the cards to focus on proving within their group. I had them write their individual thoughts about the 3 cards in their journals before starting to work together. In class tomorrow they will prove the placement of their 3 cards to the class (aka jury). Here are the beginning workings of their proofs:
Before we left for the day, I asked them to reflect and write about any changes they made because of their discussions or any cards their group was still thinking about. Here are a couple before and afters…LOVE the argument ones!