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Super Stairs

by Dan Meyer


Act One

  • Dan Meyer

    Dan Meyer

    December 02, 2013

    How many steps will he run on the super stairs? How long will it take him to run them?

  • Teacher note
    Have students write down a guess and share it with their neighbors. Then take a poll. Find the highest guess in the room. Find the lowest guess in the room.

Act Two

  • 1.

    What information would you need here?

  • Teacher note
    The language is here is really important. Students may use "steps" and "stairs" interchangeably. To keep things from getting out of control, my class decided "stairs" were physical and concrete while "steps" were the actions the person took.
  • Teacher note
    Write everything down that they want. When they ask how stairs there are, ask them to write down and share a guess. Then tell them there are 21 stairs.

    When it comes to questions of speed or rate or times, tell them to pull out a watch or a cellphone timer and then play the act one video back for them as many times as they want.

    Some will want to time the "turn arounds." Some will get different rates for going up the stairs and down the stairs. Some will time the regular stairs. Some will time the super stairs.

    Feel free to say to them at some point, "We will all have different answers and we will all be wrong. That's the nature of modeling. We're making assumptions. The question is whose assumptions were best."
  • Teacher note
    Have struggling students create a table and track "stairs" and "steps on that trip" and "total steps after those trips." Their goal will be to find a number rule that turns "stairs" into "total steps. It's (stairs)*(stairs+1).
  • There are 21 stairs.

Act Three


  • 2.

    If someone wanted to run 1,000,000 steps, what kind of super staircase would that require?

  • ImageStudent Work #1
  • 3.

    The above student found the answer to the original question a different way. Is she right? Why or why not?

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