Exponentials Lesson 1 Episode 7 (Teachers)

Reflecting

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The students describe how a beanstalk is growing between Days 100 and 102.


Episode Supports

Students’ Conceptual Challenges

While not present in this video, you should be mindful that some students may initially struggle to generalize the idea that the growth rate from one day to the next is always constant. In other words, they might not easily recognize or understand that the growth rate from Day 0 to Day 1 is the same as the growth rate from Day 100 to Day 101. This is an important idea that students need to grasp to fully understand exponential functions.

Focus Questions

For use in a classroom, pause the video and ask this question:

[Pause the video at 0:29] Draw a sketch of what you think the beanstalk’s height will be on each day from Day 100 to Day 102. How are you representing the growth of the beanstalk over each successive day? How does the beanstalk’s height on Day 101 compare to its height on Day 100? How does the beanstalk’s height on Day 102 compare to its height on Day 100?

Supporting Dialogue

[Pause the video at at 1:24] Ask students to compare their work to the work of Josh and Arobindo from the video. What similarities and differences do they notice? Ask them to explain to a partner or their group where they see the growth rate from the context in the visual representation created by Arobindo and Josh.