Frosty the Snowman (1969)
"A discarded silk tophat becomes the focus of a struggle between a washed-up stage magician and a group of schoolchildren after it magically brings a snowman to life. Realizing that newly-living Frosty will melt in spring unless he takes refuge in a colder climate, Frosty and a young girl who he befriends stow away on a freight train headed for the north pole. Little do they know that the magician is following them, and he wants his hat back. This animated short is based on the popular Christmas song of the same name."