CROSSED SWORDS AMC's Academy 6, Beacon Mall 3, Capital Plaza, Fair City Mall 3, K-B Baronet West, K-B Studio 2 and Roth's Randolph 1.

"Crossed Swords" is a new version of "The Prince and the Pauper," Mark Twain's fantasy set at Henry VIII's court, and midway through it a character strolls through the woods humming "Greensleeves" to himself. Touches like that make life worthwhile to a parent who finds himself at a children's movie.

In fact, this is a very good children's movie. There are liberties taken with the history, liberties taken with the literature - actually, the literature took liberties with the history before the movie ever got to it. Twain had Edward VI becoming a just and democratic king as a result of having changes places wotj a slum kid, a character Edward did not live long enought to disprove.

But in an atmosphere of verve and humor, the film makes Twain's points: clothes make the man, the verdict of madness depends on your circumstances, who you are depends on what people percieve as much as what you know, rank has its disadvantages but still stacks up well against the alternative, getting used to it. The child can take his pick. But any of it is bound to be more thought-provoking than the usual good guy-bad guy stuff, and the rich atmosphere of Tudor England is a sensuous treat after the sterility of The Future.

Mark Lester, in the dual-title role, is a more pretty thanbrilliant, and the acting ranges from an individualistic George C. Scott tramp-king to an average Henry VIII by Charlton Heston (Henry VIII standards, from Charles Laughton to the BBC, are high), to a Raquel Welch court lady bordering on the camp; we get a Rex Harrison cynical but kindly Duke of Norfolk, and an energetically bad daddy Ernest Borgnine. But there is a plus, in such a film, just to see so many all-star growups trying their best.

And as another treat for the parent, there is running comment on it all supplied by the superior gaze of a red-haired teenage girl who obviously could do everything right if only she got the chance. She is Edward's half-sister, Elizabeth Tudor.