by 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 noteHave 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.
What information would you need here?
- Teacher noteThe 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 noteWrite 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 noteHave 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.
If someone wanted to run 1,000,000 steps, what kind of super staircase would that require?
- ImageStudent Work #1
The above student found the answer to the original question a different way. Is she right? Why or why not?