SAN ANTONIO – Watch the video of Sarah’s school science experiment in the video player above.
Hello parents, teachers and students! Science with Sarah is back for the 2026-2027 school year, and we’re starting the year with this cool classic: Here’s how to make ice cream at home. A great way to explore changing states of matter!
Be sure to check out GMSA@9 on Wednesdays when KSAT Meteorologist Sarah Spivey does the demonstrations and explains the science behind it. To view, click on the video player above. Check out our Science with Sarah webpage for more fun science experiments!
HERE’S WHAT YOU’LL NEED
- 1 sandwich ziplock (no slide seal)
- 1 gallon ziplock (no slide seal)
- 1 cup half & half
- ½ teaspoon vanilla extract
- 1 tablespoon sugar
- ¼ cup salt
- Ice
- Spoon
- Cloth to protect hands
MAKE YOUR HYPOTHESIS
How long will it take the ice cream to form?
DO THE EXPERIMENT
- STEP 1: Pour the half & half, vanilla extract, and sugar in the smaller ziplock bag. Try to remove as much air from it as possible, and seal it tight
- STEP 2: Put enough ice in the large ziplock bag to fill it up about half way, and pour in the salt
- STEP 3: Place the sealed small ziplock inside the large ziplock, and then seal the large ziplock
- STEP 4: Using the cloth to protect your hands, shake the bag for several minutes (at least 3 minutes!)
- STEP 5: After a while, open the small ziplock and enjoy your tasty treat!
HOW IT WORKS
The salt lowers the melting temperature of the ice, allowing a very cold solution to surround the bag with the ice cream mixture. As you shake it, it causes the cream to freeze. This is a great example of how a liquid (cream) can turn into a solid as it freezes!
APPLY FOR SCIENCE WITH SARAH
Want Sarah to come out to your school? Here’s how to apply: CLICK HERE.
