My mother has been teaching a science class in summer school, and one of the activities she did with her students was making butter from scratch. I postulated that putting a churner inside the container along with the heavy cream while shaking it would speed up the process, but my mother says it has no affect whatsoever. Is there an experiment I can do to test this hypothesis? I'm a bit hung up on how to make the shaking constant, seeing as two different people would shake with a different force as would one person using two different hands.

she`s right, shaking doesn`t help, it breaks up the fat molecules too much and you want them to join each other instead, shaking will just make whipped cream and be useless afterwards.

you could try 2 samples in an erlinmyer flask one with a magnetic stirrer and the other on an eccentic, you could always get an old spin dryer and put a sack of housebricks inside it, that`ll shake a gallon or 2 )