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Guide Index

Sunrayce '93

The Turing Test

Battle of the Crazy Machines

Human-Powered Submarines

Contest Extra
in the classroom

Battle of the Crazy Machines

MIT's Intro to Design begins with a box of junk. Students have six weeks to turn their kits of assorted machine parts and motors into a machine that performs a certain task. In the program you're about to see, the vehicles have to deliver a load of ping-pong balls into a tube -- while fending off an opponent's machine. This annual student engineering competition is the ultimate test of inventiveness and ingenuity.

Curriculum Links
Activity 1: Catapult Your Creativity
Activity 2: Tower Demolition Derby
A Challenge for Seniors and Sixth Graders



energy and
work machines

volume and




Challenge your creativity! Like the MIT student engineering competition seen on Frontiers, these contests also begin with kits of assorted materials.


Your group will be given 20 minutes to build a catapult with the materials listed. Your catapult must be able to launch a ball of clay and issue more than one launch. The catapult that throws the furthest and most accurately will be the winner.


Your box of supplies should contain these items:
  • 5 rubber bands (various sizes)
  • 1 roll of masking tape
  • 4 quarter meter sticks (cut-up meter stick or sturdy piece of wood, about 25 cm long)
  • 10 paper cups
  • 15 wooden craft sticks
  • 5 plastic spoons
  • 1 pencil
  • 1 container of Play-doh

  1. No one may open the box of materials until told.
  2. Team members may not trade any items with any other team.
  3. You have 20 minutes to build the catapult.
  4. You may use only one hand to hold or fire the catapult.
  5. No one may disturb another team's catapult.
  6. The team that has the longest distance in each round will remain in the contest until a longer distance is achieved.
  7. The longest and/or most accurate shot will be the winner.

Note: One way to set up this contest is to compete three teams at a time. Then have the winners from those teams compete against each other. If a tie is declared, hold an accuracy test instead of a distance test to determine the winner.


Your group will be given 35 minutes to build a tower with the materials listed. Your tower must be able to withstand being pelted with balls of clay. The group with the tallest tower still standing after the clay balls have been thrown is the winner.


Your box of supplies should contain these items:
  • 30 pointed toothpicks
  • 50 straws
  • 1 deck of cards
  • 4 paper cups
  • 1 stick of glue
  • 1 piece of string (1 meter)
  • 1 roll of masking tape or 1m tape wound around a pencil
  • 1 pencil
  • 1 balloon (9-inch works best)
  • 25 wooden craft sticks
  • 4 hex nuts (for weight)
  • 25 paper clips
  • 3 rubber bands
  • stapler
  • scissors
  • containers of Play-doh

  1. No one may open the box of materials until told.
  2. Team members may not trade items with any other team.
  3. The tower should be attached to the box.
  4. You may not disturb, disrupt or destroy any towers built by other teams.

Note: Each group should choose a sharp shooter. The captain draws a number from a hat, and the sharp shooter throws Play-doh balls (about 1-inch in diameter) at the selected team's tower until one hits it. After all towers have been hit once, they are measured and the tallest one standing wins. Boxes should all be the same size.

  • Each spring, sixth-graders in Medina, Ohio, are challenged with a scientific competition. But it's not their teachers who issue the challenge. It's high school seniors at Medina's Buckeye High who design, coach and conduct the competition for elementary students. Like the MIT event, these contests begin with a box of assorted parts. Buckeye science department chair Randi Scalf has been running this program successfully for several years. Two of the activities designed by her students appear in this guide. Here, she explains how the process works.

  • In the fall, I divide the seniors in my bio-chem class into three groups and give them the previous year's task. (See sample activities in this guide.) They brainstorm ideas and begin to develop their own competitive ideas. They compete with each other using the same rules and supplies that the previous year's students created. They must figure out what will work and what won't, what they can get and afford and what rules will create the best competition.

  • I put each group in charge of one of the elementary programs. My objective in going to the elementary school is to provide high school students with an opportunity to be the teacher and decision maker. It is exciting to help them learn to be problem-solvers and find out how much they care about working with the younger children.

  • I split sixth graders into groups of five or six, based on how many seniors I have. Each senior has a group and if the group wins, they receive a prize, too. Even though my students test the contest idea, no project ever turns out the way any of us think it will. There is so much chance and variance that no one ever guesses the winner. Every year my students change this activity in positive ways and make it into their own design.

  • The sixth graders become so involved with what they are doing and care so much that nerves alone can be their demise. They also have their creativity turned on while having fun.

  • On contest day, we arrive at the elementary school early in the morning. We only schedule two hours for the event, so the seniors have organized as much as possible in advance. The sixth graders come to the gym wearing name tags that have been numbered so they can be put into their groups quickly. The seniors hold a short introductory program to explain what will be happening. They allow the groups to work for half of the remaining time, during which one sixth grader from each group is elected as a captain. Captains are given a few minutes to walk around and see what the other groups are doing. Then teams have a chance to redesign and practice. Once the competition begins, it is run by the students.

  • I have found over the years that some things work better than others. When the elementary students work as a small group, they are more willing to take risks and enjoy the competition more. When my students have a stake in their group winning, they generate more excitement. When my students design something that worries me early on, they work harder to refine it and enjoy the challenge more. They have never thought of something that we couldn't eventually get to work. I have found my seniors to be wonderful problem-solvers and they always think of things I'd never think of on my own. So when I am asked, "What are your students doing this year?", I can only say, "I don't know -- they haven't thought of it yet."


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.