Summertime and ice cream go hand in hand (along with summer STEM activities!). But how about making ice cream in your hands?
That’s exactly what we are going to be doing today with this ice cream in a bag science experiment.
Making ice cream in a bag with just our hands.
Or your kids hands. The ice cream in a bag science project is always a fun summer science activity for kids!
And you will also find the ice cream in a back science lesson plan below.
Ice Cream in a Bag Science Experiment
If you have cream in your refrigerator, it’s time to transform that into delicious ice cream. This is also an awesome way to learn the melting point of ice.
All three of my kids looked at me sideways when I added salt to the bag of ice. This was the perfect time to talk about the freezing point of ice and how we get ice cream from doing so.
For another fun variation on this project, try making sorbet in a bag!
Ice cream in a Bag Science Lesson Plan
Here’s the sciency bit.
Salt when added to the ice cubes lowers the melting point of the ice, just like it does when we add salt to roads in the winter.
In order for the ice to melt, however, it has to absorb heat from its surroundings like the ice cream in the bag.
The ice pulls the heat away from the cream which allows the cream to freeze and become ice cream.
If you made this with ice cream without salt you would notice that the ice cubes do not melt as much in the five minutes of shaking and you would notice that the cream is not becoming solid and turning into ice cream.
What you need for the ice cream STEM activity:
- 1 gallon Ziploc bag
- 1 sandwich bag
- 1 tbsp white sugar
- 1/2 tsp vanilla
- 1/2 cup of whipping cream
- 1/3 cup of coarse salt
- ice cubes
If you don’t want to use cream, you can also make a dairy-free ice cream in a bag experiment using apple juice! The slushie in a bag experiment (AKA, sorbet in a bag or sherbet in a bag) doesn’t have any dairy and is safe for kids who can’t have cream!
Tips & Tricks for the Ice Cream Science Fair Project
Alternately you could make this ice cream with some chocolate syrup in the bag to make chocolate ice cream, which I had planned to do, but forgot to buy the chocolate syrup. Or strawberry syrup.
Make sure you do up the small bag first so you don’t have melted ice cubes when you add it to the large bag.
If you suspect your child will drop the bag, double up the large bag, it will easily get holes when dropped – even the brand name bags. Plus, not quite as cold on the fingers.
And, to make it fit for a science fair, make sure to test variables like amount of ice, amount of salt, or different shaking methods!
Let’s Shake Ice Cream
In your sandwich bag mix together the whipping cream, sugar, and vanilla. Seal the bag, letting out as much air as possible.
In your large bag, fill it with 2 trays worth of ice cream and 1/3 cup of salt. Add your sealed sandwich bag into it and seal it, getting most of the air out of the bag.
Now shake. Shake for about five minutes. We used oven mitts because it gets quite cold on your hands after a minute.
After shaking for five minutes put it in your freezer for half an hour.
After half an hour in the freeze, scrap/shake your soft serve ice cream into a bowl. Top with some sprinkles, or chocolate syrup and enjoy. There is nothing like a little ice magic to make a yummy summer snack.