Thanks for the suggestions. I'm looking for things more like Sylvester and the Magic Pebble, where Sylvester wishes to be turned into a rock and is. Or Brush, where a boy wants a pet and ties a Brush to a string and the Brush starts to act like a dog. Or The Little Rabbit that Wanted Red Wings, in which a rabbit wishes he were different types of animals, ends up sprouting red wings, etc.