Teenage Mutant Ninja Turtles: Mikey's Monster

Mikey's Monster (Teenage Mutant Ninja Turtles) (Step into Reading) - Hollis James, Patrick Spaziante

Mostly a retelling of the same episode, but left a lot of the details found in that medium out.  I liked the message of being compassionate that it taught, and my son really enjoyed it as well!