How can I summarize the purpose of Plato's Apology and how it might connect to my life in a paragraph or two?
Plato's Apology was written shortly after the death of his mentor, Socrates. It follows the literary conventions of the "apologia", a term that means a defense, especially in a legal setting. Note that this does not mean an apology in the modern sense of saying one is sorry for having done something.
The Apology is not a verbatim transcript of what Socrates actually said at his trial, but rather a written text by Plato, using Socrates as a character and the situation of his trial to defend both Socrates himself and his followers from accusations of impiety. Because it is one of the most simple and least technical of Plato's works, it also serves as an introduction to Socratic and Platonic philosophy. Perhaps what makes the work so important is that it illustrates on both a biographical and philosophical level the importance of the quest for truth and knowledge.
As to how it is personally connected to your life, that is something only you yourself can determine. As you read the work, you might find Socrates' statements about the importance of honesty and refusal to pretend to knowledge he did not actually possess a good starting point for thinking about schoolwork.