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Standard 1: Make Sense of Problems & Persevere in Solving Them

Clip 7/29: Standard 1: Making Sense and Perseverance Using Measurement Part E4


Mathematically proficient students understand and use stated assumptions, definitions, and previously established results in constructing arguments… Mathematically proficient students are also able to compare the effectiveness of two plausible arguments, distinguish correct logic or reasoning from that which is flawed, and—if there is a flaw in an argument—explain what it is… Students at all grades can listen or read the arguments of others, decide whether they make sense, and ask useful questions to clarify or improve the arguments.

Tracy Sola presents the students with two different strategies that were used by groups in the class. She asks students how the strategies are different and what that means for the accuracy of their measurements. She then probes deeper for students to explain what each group did.

Through Tracy’s questioning, she engages students in the beginning stages of Math Practice Standard 3. The students are trying to compare two strategies and analyze the reasoning behind them. The students are starting to experience what it feels like to listen to a classmate’s strategy and decide whether it makes sense. 

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