Put some heavy whipping cream in a babyfood jar with a small clean rock or marble. You may add a pinch of salt or sugar or both, if you like. Shake vigorously until it turns into butter.
I have done this with a group of four year old students with mild disabilities. One student who was particularly strong was able to actually chip the babyfood jar by shaking it so hard. That child did not need to have the rock in the jar in order to create butter. You also need to be aware of doing this activity while children are seated at the table as they might bang the jar into the side of the table and break it.
I gave each child a jar and let them each make their own butter.
(By the way, the butter was delicious and the staff ate it on crackers at lunch time for weeks afterward. It is much better than store-bought butter!)
