james and giant peach
The JR version is adapted from the full version to be performed by middle-school aged performers, and has been adapted into a roughly one-hour format, with the capability for a large supporting cast, keys have been adapted for younger voices, and comes with the full Broadway JR showkit of materials designed to assist in mounting this production at a school or youth group. With up to 30 named characters and the abiltiy to add an ensemble, this cast can grow as large as the group that wants to perform it.
The TYA version is carefully adapted to be performed by adults for young audiences - and has been carefully adapted to that a group of 9 adult actors can play all the roles and tell the story completely for an audience of children. Both come with a performance accompaniment CD specific to the version of the show.
Short version: JR is designed to be performed by younger actors. TYA is designed to be performed by adults for younger audiences.