Algebraic Expressions Lesson 3 Episode 1 (Teachers)

Making Sense

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ET and Haleemah make sense of the game app context and think of a way to find the total amount of money spent by a group of friends on several game apps. 

Episode Supports

Students’ Conceptual Challenges

In this episode, Haleemah is grappling with what an equation is supposed to look like. On the one hand, she was able to write and make sense of expressions and equations containing multiple operations in previous lessons. On the other hand, she seems unsure about writing an equation with multiple product expressions in this episode [5:08]. Haleemah is likely just beginning to see expressions (such as 3 • 2) as both a process (i.e., a set of steps to compute or perform) and as a product (i.e., a mathematical entity unto itself). This transition is an important one for algebra, where expressions like 3x and 7y abound.

Focus Questions

For use in a classroom, pause the video and ask these questions:

  1. [Pause the video at 2:16] Solicit ideas from your students for this context. Ask them about the kind of apps they purchase, expensive apps they’ve seen, and other ideas or prior experiences they have with phone/ipad apps.
  2. [Pause the video at 3:34] Haleemah asks an important question. Rephrase it for your students by asking “How would you respond to Haleemah’s question, which is how can we write an equation for this situation if every app is $2?” Encourage students to justify their answers by explaining their own reasoning.

Supporting Dialogue

At [5:08], the teacher asks Haleemah to put together her three mini equations at the top of the table into one equation. Haleemah says it would look “kind of weird.” After writing it, she says it looks weird because  it’s “very long.” Prompt students to discuss what they think Haleemah might mean. Ask them if they think such an equation looks “kind of weird” and if so, why.