Here is a superb Cantata-Musical for children by Michael Hurd for unison voices and piano with guitar chords.
A free-and-easy style of performance is appropriate for this extremely popular cantata-musical about Jonah and the whale. The story of Jonah is brought bang up to date in this jazz form musical which children of any age will love.
The score is for unison voices, narrator and piano (with chord symbols). There are opportunities for a suitable group of jazz instrumentalists to use the piano score as the basis for improvisation, and there's even hand clapping and finger clicking for the singers!