We got started on this whole taekwondo thing as a family about two years ago. It was my reaction to Thing One coming home and telling me that a boy in his class was getting physical with him. First Thing One started taking the classes, then Thing Two, then me, and last Petunia.
Thing One is not a leader by nature. In general, he's not one to stand up for himself either, although he will defend a weaker friend long before he'll defend himself. I was concerned that he would be a doormat, one of those kids who gets pushed around at school. He's a big kid for his age, too, but this didn't seem to matter much as a deterrent.
Anyway, I signed him up for taekwondo mostly for the self-defense element of it. I want my kids to know what to do if somebody comes after them. The rule is that they may not swing first, but they may swing second (and hard) with my full blessing regardless of what the school thinks of the matter. Sometimes deliberately breaking a rule is worth it in the long term, after all.
At any rate, Thing One told me today that some jerk kid on his bus was picking on him, and finally aimed a shot at his groin. He reflexively blocked the hit (!) and then delivered a solid strike to the kid's shoulder (!!) which put the little turd in his place. He sulked off whining after that. Frigging GO THING ONE. Way to stand up for yourself...you made your mama so proud today. And hopefully that little punk will think twice about messing with you in future, too!