Clip 40/41: Standard 3: Construct Arguments & Critiques Using Quadrilaterals Part 2F
Overview
Mathematically proficient students understand and use stated assumptions, definitions, and previously established results in constructing arguments. They make conjectures and build a logical progression of statements to explore the truth of their conjectures.... They justify their conclusions, communicate them to others, and respond to the arguments of others... Mathematically proficient students are also able to ... distinguish correct logic or reasoning from that which is flawed, and—if there is a flaw in an argument—explain what it is.
Once each group has worked through the reasoning of the proof, Humphreys checks in with the group and instructs them to begin designing a poster that will display the proof they had created. Groups are instructed to design a poster that contains a drawing of the figure, the conjecture of what is to be proved, a list of the given from the conjecture, and what needs to be proved. The students can use a two column or a flow chart format of the proof. This clip is also indicative of standard 1 (make sense of problems & persevere in solving them) and standard 6 (attend to precision).