I think the difference is that Willy Wonka's the more recent version and is more in depth for Charlie's background than Charlie and the Chocolate Factory. Personally, I think the older version was much better :]

I've always been interested in this show.

Both Willy Wonka JR and Willy Wonka KIDS are now available to license from MTI. MTI's Junior Titles are approximately 50-60 minutes in length, and are edited carefully (and music arranged for) middle-school aged performers/singers. MTI's Kids Collection titles are about 30 minutes in length, and are designed for younger performers - elementary school aged. The storyline remains the same, and most of the same songs are in both versions, although the KIDS version has shorter/simpler arrangements.

There is not a "Willy Wonka Kids" as of yet...coming we hope. Besides the full length version, the Jr. version is the only musical arrangement of it. Hope you try it out!

I may be wrong, but I believe that the script for Charlie & the Chocolate Factory is a non-musical. Willy Wonka Jr. is based on the film and has the music from the Gene Wilder film version. Songs like "The Candy Man," "I've Got a Golden Ticket," "I Want It Now!" etc, by Leslie Bricusse.