Making Ice Cream in CLASS

There are a few methods of ice cream making for a classroom. All take use of the "freezing point depression" of a salt-ice mixture. In other words, salt water freezes lower than water so the ice cream mixture will solidify quicker! Here's the basic classroom setup:

  1. Materials List PER GROUP of 3.
  2. Procedure
    1. Find a partner who showers frequently.
    2. Cover the work area with paper unless you want to clean up alot of sticky stuff later.
    3. Put the milk, sugar and vanilla (and optional flavoring) into the small ZipLoc. SECURELY zipper that bag!
    4. Fill the large ZipLoc half way with ice.
    5. Pour the rock salt into the bag. Take temperature reading.
    6. Place the small bag into the large bag and SECURELY zipper this one, too.
    7. Put on gloves, unless you are a real man, and get ready to witness a phase change.
    8. Take turns flipping the bag. Hold the bag by its corners and keep the bag flipping over and over. This will take 10-15 minutes to freeze. Take the temp reading a few more times at 3 or 5 minute intervals.
    9. When you have "solid" ice cream, remove the inner bag and rinse off with very cold water. DO NOT spend alot of time rinsing since this will melt the ice cream. A quik rinse is fine. Discard the outer bag and contents in trash bag. DO NOT DUMP IN SINK. Rock salt can hang around for a while and corrode old pipes.
    10. Dish out and enjoy!
    11. Clean up and share!
  3. Questions to ask.

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