One of my all time favorite favorite books is The Giant Jam Sandwich. It's one of those books I've probably read 300 times. I have found newer copies at yard sales, but I like my copy. It's mine from when I was little and it's not in great shape.
Anyway. I love it and I read it to my preschoolers. Then we made butter.
Last year, I asked the parent helper to bring homemade bread in because I knew she'd love to. This year I asked the parent helper to bring bread and let her decide what I meant. We ended up with store bought bread and it worked all the same. I brought the jam. I have a large batch of two years ago low sugar (blah) strawberry jam to use up.
The kids made butter in baby food jars. This is the third year I've done it this way and it works well. The glass jars are becoming harder to find, but I have a large hoard in my basement. I used them for applesauce in the fall at preschool too. I really have to clean them well, my grandpa used to store nails in them.
About 2T heavy whipping cream and a dash of salt are placed in a baby food jar along with a marble. The lid is attached securely and I wrap a paper towel around the whole thing and the kids shake the jar. And shake and shake and shake. I played some shaking and jumping songs to help keep them moving. There's always someone who pops the top up and it leaks, but otherwise it's pretty easy.
They shake until they can't hear the marble. They brought it to me and many had to be sent back for more shaking. They get a little tired. It takes about 5 minutes of kid shaking. Some of the kids end up with a whipped butter, but if they shake through that, it really does resemble a traditional butter. This year we did have one jar break. That marble popped right on out. I've never had that happen before but I assume there was an issue with the jar prior to our shaking.