All subjects and topics related to self-development, even concepts such as NLP and psychotherapy.
The official site:
Theselfdefenseco.com
And remember:
Whether you're 16 or 18, or 21, or 30 (or older), you should be responsible for your own actions. In the US, killing or injuring somebody in self-defence, especially witnessed by somebody, and correctly reported, can go unpunished, while in Europe many countries for killing/injuring in self-defence will give you a sentence.
Regarding the law, the how-to of stopping somebody without injuring/killing him should be specially taken care of.