This is quite well-written, both stylistically and grammatically. Your first sentence is a bit too long, though, and should be broken into two or more shorter ones. Also, you might want to discuss in a bit more detail how you went from "hesitant" to "confident" in your social interaction. The transformation is rather abrupt and inexplicable at the moment. Finally, writing with a strong style, as you do, can disguise the problem of over-reliance on weak verbs, but it remains a problem nevertheless:
"Moving from the suburb of Conyers, Georgia to New York City
was a difficult transition. As we entered Brooklyn, the crowded streets
got my attention. Never in my life had I seen so many people in one city. It
was mind-boggling. My parents enrolled me in a private school. This school
was completely different from the magnet school I had attended. The students
were required to wear uniforms, the teachers
were a lot stricter, and, unfortunately, there
were no science fairs. On the first day of school, kids gathered in groups to discuss their summer breaks. I
was hesitant to join in the conversations"
In this section you rely too much on forms of "to be," though "got" isn't great either. Throughout the rest of the essay, you have many other weak verbs, such as "to have," to make," etc. Try revising your essay with a view to either replacing those weak verbs with stronger ones, or rephrasing sentences to eliminate instances of weak verbs altogether.
For more on using strong verbs, go here:
http://www.essayforum.com/general-writing-questions-13/impor tance-choosing-strong-verbs-6143/Sean, EssayForum.com