STEM Challenge: Design a Boat that Floats

Grab the recyclables, toss the kids in the car (gently!), and head to a local creek.

It’s a great time for a simple STEM challenge:  design a boat that floats.

This is one of our favorite STEM activities, and can be done over and over as the kids get older and their designs become more sophisticated.

If you want to give this project a new twist, check out our balloon boat challenge and see if your child can power their boat with a balloon.

STEM Challenge: Design a Boat That Floats

Our homeschool group got together at a local park with a creek to do this challenge.  You could also test your boats out in a pond, kiddie pool or even the bathtub.   Wherever you go, I guarantee the kids will have fun, and learn something too!

We spread all the materials out on the picnic tables at the shelter and gave the kids plenty of time to get creative.

Some of them chose to collect sticks to form the base of their boat.  These were tied together with a bit of twine.  (Pipe cleaners were also helpful in keeping those sticks together!)

Craft foam and card stock were popular choices for making sails.  These both hold up fairly well to a bit of water, unlike light weight paper choices.

It was fun to see their minds all working:  thinking, designing, and building.

Once they were happy with their boat’s design, it was time to decorate with stickers, permanent markers, pipe cleaners, and whatever else they found.

Then it was time to test out the boat designs!

They were thrilled to see that all the boats they designed stayed afloat.

A piece of ribbon, tied to the end of the boat was a good solution for keeping them from traveling too far down stream.

Materials to Consider for the Boat Design Challenge:

• Empty plastic bottles and plastic cups
• Egg cartons
• Sticks and straws (to make masts for sails)
• Yarn, twine, string, and ribbon
• Craft foam, card stock, and cardboard (sails)
• Duct tape, electrical tape, and packing tape
• Stickers, permanent markers, pipe cleaners, and other decorating items

Want to increase the STEM challenge?

See how much weight the boats can hold!  Pennies or small pebbles make good weights.

See how long the boats stay afloat.  Use a timer to see which boat floats the longest.  Brainstorm reasons the boat floats longer than the others.

Find ways to waterproof the boat.  Will plastic wrap work?  Packing tape?

Or, try to power your boat by making a vinegar & baking soda boat.

This STEM challenge: build a boat that floats is perfect for a wide range of ages. (And it makes a great camp craft!)

Other STEM challenges you may enjoy:

• DIY Rubber Band Boat
• Plastic Egg Submarines
• Build Your Own Catapult
• Make a Paper Cup Phone
• 30+ STEM Activities to Help Your Child Soar