I used to be 5'8.5" -- I was going with a woman who was also 5'8.5; back to back there was more than an inch diff. in heights. She was the taller one, sigh but she had legs that seemd to go all the way to her neck but I digress
I got by in school simply by being cool to everyone. But, that's not to say I couldn't handle myself with some well-placed roundhouse kicks :)
I got by in school by being crazy (well actually, i just did not perceive the world like them); I had a velour sweater - the velour was soft and fuzzy on the outside, so I wore it inside out. There were other things but I also learned that if you grab someone's elbow and press your thumb into the joint, they fall to their knees then I could walk away. If they persisted, I would grab their elbow again and when they dropped to their knees, I would poke them in that spot behind the jaw just under the ears - they usually went rag-doll after that.
Of course, they would sometimes attack me in packs and beat the crap out of me, sigh. High school in Montana was not nice to anyone who was different (1960s rural life was probably the same across the country).
I could never get my foot up high enough to kick - I always envied those guys who could (shhh, and often fantasized about women who could .. nevermind).