Use the Sink or Float Worksheet with the “Sink or Float?” science project to encourage kids to make predictions, perform tests, and record their results.

This project is perfect for indoor discovery – especially in colder months! Put a towel under a large container of water for easy clean up. If the weather is nice, try taking the experiment outdoors.

Take the project further by testing even more objects. You may need to print out multiple copies of the worksheet. Here are some ideas of things to test:

  • Rubber duck
  • Tennis ball
  • Bell pepper
  • Banana
  • Empty glass bottle or jar with a lid
  • Plastic water bottle (with or without water)

Discuss with your students why some objects float and some sink. What objects were hollow inside, or filled with air? Did that make a difference? What objects did they expect to sink, but actually could float? What objects did they think would float but sank instead?

For more on density, buoyancy, and the properties of water, check out our Learn About Water Science Lesson.