Teaching Ninja: Book One (The Learning Curve)
The Learning Curve is the first volume in the Tesaihiryu Ninjutsu Series. Ninja International strives to bring each of it's students to realization of the ultimate potential. We do this by supplying each individual with the tools necessary to teach this ancient art. For the best way to learn is through teaching. Run, Flip, Climb, Fight, Leap, and Swim with Ninja International.