I used to churn butter at my grandparents places when I was a kid. My grandmothers both cooked with butter, because they MADE it. And whatever my mama fed me didn't stunt my growth. When I was 45 I could still lift an engine block, but now that I'm (almost) 52 the 8/4 hardwood I've been wrassling all week, with the overtime, has done tuckered me out.
But that exhaustion is probably something else. Only my liver knows for sure.
I remember in early elementary school, 1st or 2nd grade perhaps, making butter in class. We used heavy cream and put it in a clean glass jar with a lid and a marble inside and all of us took turns shaking it until it turned to butter. It was a science project and a very tasty one to boot as we spread it on fresh baked bread our teacher brought from home.
http://www.jumpstart.com/common/make-your-butter
Sadly, I cant imagine many public school teachers being allowed to do that nowadays butter= cows=global warming, the potential for breaking glass, food allergies, religious objections, some stupid kid might actually choke by trying to swallow the marble, live alone a teacher bringing a home baked food product that wasnt prepared in a USDA approved kitchen.