Although it looks like this site has not been updated in awhile (since 2016?), “Kids Love Short Films” has an archive of animated shorts that are considered appropriate for a young audience. I say, “considered appropriate” because I always advise that you preview any videos before showing them to a class, knowing that “appropriate” is a subjective word.
Short videos like the one above often don’t have any dialogue, so they are good for students to summarize. You can also discuss theme with your students or, depending on your curriculum, the design elements used in the film. Some may be inspiring, like the ones that I collect on this Pinterest Board, while others may be directly related to the content you are teaching.