The Slinky

CCSS: 5.NBT.B.7, 5.NF.B.4, 7.G.B.4

Georgia’s K-12 Mathematics Standards: 5.NR.3, 6.NR.1, 7.GSR.5

Ask students:

  • What do you notice?  Record student responses.
  • What do you wonder?  Record student curiosities and wonders.

Focus question(s):

  • How long will the slinky stretch?
  • How long will the slinky be if they stretch it all the way out?

Estimate:

  • Write an estimate that is too low (be brave).
  • Write an estimate that is too high (be brave).
  • Write your best estimate.
  • Place and space each of your estimates on an empty number line.

Ask students what information/tools they need to answer their question.  Give them their information as they ask for it.

7th Grade:

5th or 6th Grade:

  • Share your solution and strategies.  Compare strategies and results.
  • Do you think the actual length will be exactly what you determined? Why?
  • How reasonable was your estimate?

Watch the video below to see how long the slinky actually is when it is stretched out. Compare these results with yours.

  • Why do you think the answer you got and the actual might be different?
  • What did you do well during this task?
  • What might you do differently next time?

What if…?

  • Think of a What if…? question for this task.
  • What curious question do you have about this task, if you were to change one thing about it?
  • Example: What if it was a Slinky Jr.? How long would it be?

More questions about this task. Check out The Slinky FAQs.