6th Grade Task: Gears

6th Grade Task: Gears

Standards & Objectives

Essential and guiding questions: 

Whole Group Questions:

PART A:

  • Who can explain how you know that gear B will turn fewer times than gear A? Does it matter how many times gear A turns – will gear B always turn fewer times? Why?

PART B:

  • Many of you created a table to record the turn values. Why was this an effective way to keep track of the turns?
  • What are some of the patterns that you noticed?
  • How did this table help you establish a relationship between the number of turns?
  • What is the relationship between gear turns?
  • Did anyone find another way to keep track of the gear turns?
  • Was it more useful than a table?

PART C:

  • Who can explain how you determined the number of times gear A would turn if gear B turned once? Who used the table? How did that help?
  • Who set up an equation? How did you determine what equation to use? Who used a ratio and scaled through division or multiplication? How are these methods related to each other?

PART D:

  • Who initially thought you would add 4 teeth to both gears? Why?
  • What made you change your mind? If 4 teeth are added to gear A and 6 teeth are added to gear B, how does that connect to the relationship you saw in part B? 

Activity/Task Variations

Blooms taxonomy level: 
Understanding
Differentiation suggestions: 

Entry/Extensions:

Assessing and Advancing Questions

If students can’t get started….

Assessing Questions

  • Let’s look the gears. As gear A turns, tell me what will happen to gear B. Why?

Advancing Questions

  • If gear A turns all the way around, will gear B also turn all the way around? Why or why not?

If students finish early….

Assessing Questions

  • Show me how you determined your answer to part D.

Advancing Questions

  • If gear B turns 117 times, how many times will gear 1 turn? How do you know?
  • If a third gear C was added and connected to gear B with 15 teeth and gear A turned 5 times, how many times would gear C turn?