Mathletes Week One: Building a Mathematical Team (Favorite Number, Counting Off, Helium Stick and Hoop)

We had a great kick-off to our first week of Mathletes for the 2016-2017 season. We started with introductions and name badges asking the children for their favorite number and why. So many of their favorite numbers are connected to each other so I was able to say, for example, “two Marys is equal to one Samantha” or “4 times Ryan is equal to Sam.” My favorite number changes each day based on my experiences so early in the week, my favorite number was 21. Later in the week it changed to 42. 21 was based in the number of gears on the bicycle that was stolen from me a few days ago and 42 represented the other 21 gears of the second bicycle that was stolen from me a few days later. Apparently, my bike locks were not South End safe. This also sparked a question about engineering effectiveness for the intended purpose. This will be a theme throughout the year.


This week’s Mathlete fun work (that is Mathlete speak for homework) is to interview as many people as possible as to their favorite number and why. The worksheet I gave them to record their data did not have a column for the name of the person; they should feel free to add this. An updated worksheet is attached.


The second part of our lesson was a team building exercise on Counting Off Numbers With Eyes Closed (we did not do this with all of the groups). BTW, the children came up with several solutions to making this work; the most popular solution was for the first person to say “1” and then followed by touching the person’s knee to their right to indicate it was their turn to recite the next number.


Counting off — stand around room, now sit wherever you want; activity to close your eyes; count from 1-# of Mathletes where everyone must say one number at a time (if 2 or more people say the same number, start again); if they get to 10, go to 20.


  • What was the hardest part of this challenge?
  • Did one person take the lead? If so, was that helpful?
  • Did you feel like you were suggesting a strategy that was not heard…how did this make you feel?
  • How is this relevant to working in teams during Mathletes?
  • How did you come up with a strategy that worked?
  • Why did it take your team so long to come up with strategy?


With all groups we did the Helium Stick and Hula Hoop challenge. Of course, there was not helium in these objects but they do rise when the object is to lower them. Please try this with a large group of people if you can. Here is the description of the challenge and the questions we discussed afterward.


Helium Stick/Hula Hoop — Discuss when others have helped you to get better at an activity. Would you have done as well without their help?

Your mission is to lower the stick or hoop to the ground without losing contact with the stick or hoop. Either in two lines facing each other for the Helium Stick or a circle for the Helium Hula Hoop. Everyone must have one index finger touching the stick/hoop at all times; stick or hoop must rest on top of each index finger at all times (no grabbing or finger curling); after the group extends index finger at neck level, I will lay the stick or hula hoop on their fingers; THE GROUP MUST WORK TOGETHER TO LOWER THE STICK/HOOP TO THE GROUND; the group will start again if any one person loses contact; the stick/hoop will likely rise since everyone is trying to maintain contact; after refocusing, the group should be able to lower the stick or hoop.


  • What did you think when you were first told the object of this activity?
  • Did you think it sounded difficult?
  • How did you react when the stick/hoop began to rise?
  • Did anyone in your group come up with a creative way to solve this problem?
  • Ask the group if everyone understood the mission and technical lowering rules.
  • Ask if anyone was intentionally trying to sabotage the group's mission by lifting the hula hoop.
  • Ask if everyone sincerely wanted to accomplish the mission or thought that it could be done.
  •   If everyone understood the mission, and was committed to succeeding, why did the group get so far off track right away? Try to elicit answers that are related to the group process, not the technical explanation of the challenge. For example, "we didn't plan well" more so than "we weren't holding our fingers correctly.
  • Ask the group to share example of groups in which they have participated that seemed to be comprised of committed folks, but were not productive.
  • Discuss what types of actions are important to keep a group focused on the mission.
  • Many times during this activity, people become frustrated with others who aren't lowering the stick or hula hoop, and often choose one person as the culprit. Also, some people give up and let the stick/hula hoop come off their fingers. If either happens, be prepared to discuss how blame or giving up affects groups.


Tip for success: When you place the hula hoop on the group's fingers, apply slight downward pressure before letting them begin. This helps create the initial upward pressure that creates the "helium hula hoop." 

How Does it Work?

The stick does not contain helium.  The secret (keep it to yourself) is that the collective upwards pressure created by everyone's fingers tends to be greater than the weight of the stick.  As a result, the more a group tries, the more the stick tends to 'float' upwards.


The last challenge was to understand RPMs or revolutions/rounds per minute with spinning my circular white board on my finger. The children were asked to estimate the radius of the white board (14”) and then created a beautiful work of modern art by holding their white board markers of different colors lightly along the board as it was spinning. I had them make conjectures about what the result would look like. They were essentially concentric circles with overlapping orbits like Pluto and Neptune. The most interesting designs were in the middle of the board. We then discussed “radius” and I asked them to estimate how much radius I needed under the board to spin it. We then looked at the evidence when it was turned over.



It is going to be a great year. Enjoy and easy week of fun work. The harder stuff is on its way.

Favorite_Number.pdf11.49 KB