Nintama Rantarō: Invincible Master of the Dokutake Ninja

Overview:

At the Ninjutsu Academy, Doi teaches young ninjas known as "Nintama." One day, he goes out for a battle against a ninja from the rival clan, but vanishes without a trace. The Nintamas worry for Doi's safety. At the same time, the Academy receives troubling news that their rivals at Dokutake Castle may be scheming something.