Clip 23/41: Standard 3: Construct Arguments & Critiques Using Algebra Part 1B
Overview
Mathematically proficient students understand and use stated assumptions, ... 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. Students at all grades can listen or read the arguments of others, [and] decide whether they make sense...
Disston asks his students to focus on a category of symbol strings (expression, equation, inequality), separate them, and discuss how they know how to categorize them. Students are asked to make statements like "I know this is an equation because..." or "I think ... what do you think?"