Solson Publishing released a series of training manuals during the apex of the Turtles popularity. Some issues even had exclusive Kevin Eastman and Peter Laird drawings.
Comics
Teenage Mutant Ninja Turtles: Martial Arts Authorized Training Manual #1
Martial Arts Authorized Training Manual: Michaelangelo #2
Martial Arts Authorized Training Manual: Donatello #3
Martial Arts Authorized Training Manual: Raphael #4
Martial Arts Authorized Training Manual: Leonardo #5
Teenage Mutant Ninja Turtles Teach Karate #6
How to Draw The Teenage Mutant Ninja Turtles