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8th Grade Math - Representing Constant Rate of Change

Clip 5/17: Rate of Change: Lesson Part 1A


Antoinette Villarin begins her lesson on graphing constant rates of change by reviewing the learning goals and mathematical practices, naming Standards for Mathematical Practice 1, 3, 6, and 7. She notes that it is important that her students understand how to build a mathematical argument, and she shares sentence frames and key vocabulary that the students will use as they build their arguments.

Antoinette presents a model of two bottles attached to each other so that fluid can flow between them, and she asks her students to make sense of the problem by describing what they see happening.

Students share that as the amount in the top container/prism decreases, the amount in the bottom container/prism increases.

Teacher Commentary

Cecilio and I talked about "What can we anticipate kids doing?", and that's how we started planning the lesson. We looked at the pre-assessments from all my classes, thinking about how we wanted to start this lesson. I'm thinking when you base your planning on that, then you know exactly what you're looking for. When your intention is really specific, you become more interested in what students are doing.

Materials & Artifacts