One of my youngest nephews is giving off the vibe that he is being bullied at school. Nothing solid, just lots of little signals.
The landscape for martial arts changed since I was a kid. Back then there was boxing, judo and karate.
Now there is Brazilian Jiu Jitsu and Krav Maga, Taekwando and Aikido and a dozen others.
Some of them are too brutal to hand to an eleven-year old boy. Others are more like stylized dancing than combat. Nevvy doesn't need to rip off arms or crush anybody's trachea. On the other hand, he doesn't need to learn the 243 choreographed "bird" moves when the bully probably needs little more than a stiff poke in the nose with a right-cross.
Some Dojos and Sensei emphasize self-control and discipline more than others. Some focus on the mechanics more than the responsibilities.