From a time travel perspective, the best surprisingly turns out to be Harry Potter and the Prisoner of Azkaban.

This is surprising because the book made a critical temporal error which the movie fixed almost accidentally.  (Efforts to repair the book (a book entitled Time Travel and Harry Potter by Richard H. Jones, our review of which is apparently lost with the demise of Gaming Outpost) have not been successful.)  The major time travel incident is resolvable despite its apparent problems, once we recognize that Hermoine, not Harry, is the principle time traveler.

It is probably appropriate for children about the same age as the characters in the book (thirteen) and older.

In a close second, Flight of the Navigator manages to tell a very clever and entertaining story of a boy taken to another planet for eight years and returned home to create quite a stir, all of which is resolved when he is returned to his own time.  It gives us the "AB" side of the anomaly, leaving us to reconstruct the "CD" side, and the possibility exists for some terrible disasters, but they also can be resolved relatively simply if the main characters take some simple steps to do so.  This is a more serious adventure story, reminiscent of such films as Cloak & Dagger or E.T., in which the story is serious and a bit frightening, but the heroes are kids.  The science is a bit off in some places, particularly when NASA tries to explain how Einstein says it would be possible to travel five hundred sixty light years in eight years.

This is suitable as a general family film.

Teenage Mutant Ninja Turtles III, commonly known as Turtles in Time, is another fun movie, action packed but with a sort of cartoon violence in which no one really gets hurt except the villain.  The time travel elements are complex and difficult to resolve, but the problems are easily overlooked even if resolving them requires serious effort.

This again is probably a family film, suitable for the young, although the very young might be a bit bored by it.

It happens also to be the last project on which Jim Henson worked before his death, although it is not a Muppet movie by any means and his contribution was part of making the turtles come alive.

One of our fans called attention to The Last Mimzy, again a serious adventure in which kids are the heroes.  The problems, temporally, in this film are extremely challenging, and although they are not insurmountable the probability of time being preserved seems extremely low.  Otherwise it is an enjoyable film with some interesting ideas.  Some parents might be concerned at the film's efforts to explain aspects of mysticism and psychic ability with future science.

It is another family film.

Honorable mention goes to Disney's recent Jim Carrey version of A Christmas Carol.  Although it tells the serious and at times frightening traditional ghost story, it uses a realistic animation format to make it both more accessible and more entertaining for younger audiences while maintaining the story including much of the wonderful Dickensian dialogue.

There are other time travel films suitable for children, but none which have caught our attention as worth viewing.  It probably should be mentioned that despite being animated, Bender's Big Score is not suitable for children, being laced with the sort of adolescent humor that is offensive to intelligent adults, as well as being a (probably intentionally) disastrous time travel story.  If you are a time travel fan looking for films for your children, the others are a good place to start the introduction to the genre.  If you have a favorite time travel film I might have missed, please let me know by e-mail or in comments.