I have accumulated a large number of the freezer gel packs from a meal service. I’d like to find a way to use them in a classroom activity.
—P., Georgia

The best thing about these freezer packs is that they provide a constant that will help your class design and conduct a lot of experiments. Reusing these in your classroom is also a great environmental message.

A few ideas for experiments :

• Engineer the best picnic cooler. (Save styrofoam boxes and pellets from shipments you have received).
• Determine the optimum place to put a freezer pack in a standard cooler.
• What conditions speed up/slow down warming or cooling? Correlate the data with ambient temperature.
• Investigate the heat conductivity of different solids and liquids. Put the packs in ziplock bags and immerse them in oily/messy liquids.
• Surface area experiments: curl them up, lay them flat, stack them vertically/horizontally, spread them out. Relate this information to physical science, chemistry and even biology.
• The contents of freezer packs are non-toxic. Open them up and do carbohydrate, lipid, protein, and other chemical tests on the contents.
• Place them on different parts of the hands and arms to create a cold sensitivity map.

As useful tools:

• Keep them in the freezer to use instead of ice cubes for chemistry or biology activities.
• Putting live insects in a freezer for a few minutes will slow them down. Place the gel packs under the insects to keep them cool while observing them with microscopes or magnifying glasses.

Hope this helps!

Photo credit: By Dhenning2005, aka Dave Henning [Public domain], from Wikimedia Commons