Random House Books for Young Readers, 1988. — 48 p. — (Step into Reading) — ISBN: 978-0394893846.
The unusual purple rock that Bob has found begins to talk, telling him that it fell out of a space ship and needs Bob's help to return to the planet Kal-dor. The subject matter will help lure problem readers and the simple vocabulary will keep them going. Vivid watercolors will add to children's enjoyment.