We had homemade ice cream for dessert on Thanksgiving. (My dad, never having seen our machine, asked, "Whose home was the ice cream made in?") But the machine we have uses a cooling pan with some kind of chemical sealed inside. You put the pan in the freezer before using it, then just add the ingredients and let the machine stir them up. Not much to it.
Meanwhile, over at Socks and Books, homeschoolers "Moomintroll" and "Snufkin" recently made ice cream the old-fashioned way, using rock salt and ice cubes. We did this years ago using two plastic bags, but they used a metal pot, which I think looks way more dramatic.
Go to their post to see how its done, complete with chemistry explanation. I'm saving this link for future reference!