My World.

After years of attending the same school, following the same routine, and wearing the same uniform, I found myself in a place where only black and white existed;

Switched the comma and semicolon.

I began to involve myself in various activities at school; I signed up for more interesting classes than the ones I was required to take freshman year; and I befriended out of the ordinary and somewhat odd people.

I feel like you're overusing the semicolon. Replace the first one with a regular colon, then replace the second with a comma? You could insert one before the next sentence, though.

As a personal essay, I feel like it's lacking something, but I'm not quite sure I can put it into words. What's the maximum length, and how long is it now?