Simple physical changes are ideal subjects for teaching kids about forming hypotheses.

The purpose of a science project isn't simply to amaze people with fancy displays, it's to show your understanding of the scientific process. You can guide your second-grader through this process of forming and then proving a simple hypothesis that relates to his or her studies of the states of matter: that by controlling temperature you can control how fast ice will melt.

Forming the Hypothesis

Explain to your child that a hypothesis isn't just a guess; it's an informed opinion that requires some research.

Help your child go online and read about how temperature causes ice to melt.

Use what he or she has learned to guide your second-grader toward the hypothesis that if you keep an ice cube in a hotter temperature, it should melt faster than an ice cube kept in a colder temperature.

Guide your child in refining the hypothesis: that in addition to higher temperatures causing ice cubes to melt faster, you should be able to control how slowly ice will melt by lowering the temperature accordingly.

Testing the Hypothesis

Preheat the oven to 180 degrees.

Help your child set the three plates side by side, and place one ice cube on each plate.

Place one of the plates in the refrigerator and another in the oven. Leave the final plate on the counter.

Check every five minutes to see how much has melted from each of the three ice cubes and if your hypothesis was correct. Record each check-up with the camcorder.

Things Needed

  • ['Internet-ready computer', 'Oven', '3 oven-safe plates', '3 ice cubes', 'Refrigerator', 'Watch or clock', 'Camcorder']


  • If you're performing this experiment at a science fair, you can use only two ice cubes: Place one plate into a cooler half filled with ice, and leave the other one out at room temperature.

    If the ice cubes melt quickly, you can repeat this experiment again. Explain to your child that repeating experiments is an important part of the scientific process because if you get the same results over and over, you know you can trust those results.

    If you don't have a camcorder, your child can snap photographs of the ice cubes with a camera.


  • Make sure not to expose the camcorder to any of the water created by the melting ice.