Proportions Lesson 2 Episode 2 (Teachers)

Exploring

Download Math TaskLink to Geogebra applet

Christopher and Kate explore how to make the red car go the same speed as the blue car when the blue car travels 10 miles in 4 minutes.  They create a table to record and test their conjectures.


Episode Supports

Focus Questions

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

1. [Pause video at 2:03] Kate and Christopher are going to use a table to keep track of their guesses. What information does their table record? Make you own table to track your own guesses and race results.

2. [Pause video at 4:45] What does it mean for an equal sign to be in the a.f. and a.l. columns. What is equal? How do you know?

Supporting Dialogue

When engaging in the tasks in class, invite your students to consider the varied student work in the room on by considering the student tables created in Focus Question #1.

1. As students build their own tables, find two different ways that the students are expressing their ideas and ask the students if they would be willing to share their work with the class.

2. As students share their work, ask another student in the classroom to compare what they heard. For example: “Can someone say how William’s and Jacob’s tables are different? How are they similar?”