How Long Can a Paper Boat Float?

Are you ready for another boat building and floating challenge? Let’s see how long you can get a paper boat to float in water before it turns mushy and/or sinks. Although this is called “Bathtub Buoyancy,” I expect you probably would want to carry out the experiment in a bowl of water or other container that could be easily set aside. This might tie up your bathtub for a day or two 🙂


  • Variety of paper products, such as oaktag, printer paper, construction paper, even newsprint
  • Test container to hold water, big enough to accommodate your floating boats (Note:  I’m sure you know to always watch small children around water, even little amounts.)
  • Optional:  clock, paper and pencil to record results

Instructions: Build some paper boats of different materials, using roughly similar designs. Set them in water and then watch how long they float. You may want to check back every hour or so for boats that are well crafted, others may go down in minutes. Think of ways to make paper boats that float even longer. Yes, you may coat the boats with paint or other waterproof coatings, but not aluminum foil. Then let me know what you find out from your experiments and once again, I’ll post the results in a week or so.

Actually, making a boat out of paper isn’t as crazy as it sounds. For an absolutely fascinating history of paper boats, check out The American Boats... It’s dense reading, but well worth the effort. I’ll talk more about it in the upcoming results post. Hope you have fun.

For a more modern take on paper boats, see this giant paper boat made by an artist at the DailyMail. (You might want to check this website for appropriateness before showing children).

Example of Paper Boat Folding Instructions

Edit: For results