Float Your Boat Challenge
Hosted by: UT Austin Mechanical Engineering Graduate Student Board
Visit our Booth: Sunday, March 7, 2021, 12 p.m. - 4 p.m.
Recommended Grades: 5th, 6th, 7th
The Challenge: Ready to float? Design and build a boat with available household materials like aluminum foil, popsicle sticks, and tape. When ready, fill a sink with water and float away!
To test your boat, place objects (like golf balls or LEGOs) in your boat and see how many it can hold without sinking. What types of objects are easier to keep in your boat? Why? How would you re-design your boat? Can you redesign and test again and see if it can hold more?
Send us a picture of your boat! What were you able to float? Share your design on Flipgrid.
Need some tips or steps for the process, head to the How To tab for some suggested steps.
- Aluminum foil
- Popsicle sticks, toothpicks, straws, skewers, plasticware, or sticks
- Rag or paper towels
- Pennies, golf balls, LEGOs, marbles, small rocks, or anything else that slowly adds weight to your boat.
- Bucket, tub, sink, or dishpan
How does this activity connect to STEM and today's Girl Day theme of Moving Around: Land, Water, Air, and Space?
Engineers have to figure out ways of getting things from one side of the world to the other. They design boats, airplanes, bicycles, cars, and other vehicles to get people and things all over the world. Each design is different and engineers must understand their design constraints (Can I only use foil for my boat or can I use other materials?) and the challenge they are trying to solve (Create a boat that holds the most pennies possible.). Engineers work in teams to perhaps maximize the amount of stuff a boat can carry, look at the science to figure out what materials will work best, consider the safety of transporting the materials, and more. And when engineers create something, they test it...and if it fails, they redesign and try again. Getting something to fail is part of the process of figuring out how to make something better. Make your tin foil boat fail...and then make it better!
This brief video explains the underlying physics involved in how boats float! Can you take this knowledge and apply it to your boat?
Below are step-by-step instructions for one way to make your boat. There are unlimited ways to get creative and to design boats that float using our suggested materials. Get creative. Design and create. Test it out. And when it sinks, redesign, recreate, retest and do it again! Enjoy the Engineering Design Process with this activity!
Step 1. Supply it
- Cut one (1) square section of aluminum foil.
- Gather four (4) supports and four (4) pieces of tape.
- Suggested supports: Toothpicks, popsicle sticks, plastic forks/knives/spoons.
- Suggested tape: Painters, scotch.
Step 2. Construct it
- In the manner you see fit, combine the aluminum foil, supports, and tape to create your boat!
- Hint: Volume is your friend. Make the hull of the boat as large as possible.
Step 3. Float it
- Fill your sink or bathtub with 4-8 inches of water. Place your boat in (gently!) and watch it sail.
- Does it stay upright? Does it leak?
Step 4. Sink it
- With the weights of your choice, slowly add them one at a time until your boat sinks.
- What objects are easier to float in your boat than others? Can you re-design your boat to hold more?
- Suggested weights: Golf balls, eggs, marbles, pebbles.
Optional: Send us a picture of your boat! What were you able to float? Share your design on Flipgrid.