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Even my middle schoolers could be successful with this activity. Take a balloon, blow it up and find the volume in warm water. Put the balloon in the freezer for an hour and measure the vo... See More

Even my middle schoolers could be successful with this activity. Take a balloon, blow it up and find the volume in warm water. Put the balloon in the freezer for an hour and measure the volume of the balloon in cold water. Use a ziploc bag to get a more quantitative measurement. Middle school students probably would have trouble extrapolating to -273 Celsius, but high schoolers should not have a problem. This activity is written for high school students with the premise that they would do this at home.