http://classics.mit.edu/Plato/apology.html
I always read that he was "corrupting" the youth, but there may be some ambiguity in the translation.
Some fun bits of dialogue (sorta):
Socrates: What do they say? Something of this sort: - That Socrates is a doer of evil, and corrupter of the youth, and he does not believe in the gods of the state, and has other new divinities of his own. That is the sort of charge; and now let us examine the particular counts. He says that I am a doer of evil, who corrupt the youth; but I say, O men of Athens, that Meletus is a doer of evil, and the evil is that he makes a joke of a serious matter, and is too ready at bringing other men to trial from a pretended zeal and interest about matters in which he really never had the smallest interest. And the truth of this I will endeavor to prove.
Socrates: Come hither, Meletus, and let me ask a question of you. You think a great deal about the improvement of youth?
Meletus: Yes, I do.
Socrates: Tell the judges, then, who is their improver; for you must know, as you have taken the pains to discover their corrupter, and are citing and accusing me before them. Speak, then, and tell the judges who their improver is. Observe, Meletus, that you are silent, and have nothing to say. But is not this rather disgraceful, and a very considerable proof of what I was saying, that you have no interest in the matter? Speak up, friend, and tell us who their improver is.
Meletus: The laws.
Socrates: But that, my good sir, is not my meaning. I want to know who the person is, who, in the first place, knows the laws.
Meletus: The judges, Socrates, who are present in court.
Socrates: Certainly they are.
...
Socrates: Then every Athenian improves and elevates them; all with the exception of myself; and I alone am their corrupter? Is that what you affirm?
Meletus: That is what I stoutly affirm.
Socrates: I am very unfortunate if that is true. But suppose I ask you a question: Would you say that this also holds true in the case of horses? Does one man do them harm and all the world good? Is not the exact opposite of this true? One man is able to do them good, or at least not many; - the trainer of horses, that is to say, does them good, and others who have to do with them rather injure them? Is not that true, Meletus, of horses, or any other animals? Yes, certainly. Whether you and Anytus say yes or no, that is no matter. Happy indeed would be the condition of youth if they had one corrupter only, and all the rest of the world were their improvers. And you, Meletus, have sufficiently shown that you never had a thought about the young: your carelessness is seen in your not caring about matters spoken of in this very indictment.
...
Meletus: I mean the latter - that you are a complete atheist.
Socrates: That is an extraordinary statement, Meletus. Why do you say that? Do you mean that I do not believe in the godhead of the sun or moon, which is the common creed of all men?
Meletus: I assure you, judges, that he does not believe in them; for he says that the sun is stone, and the moon earth.
Socrates: Friend Meletus, you think that you are accusing Anaxagoras; and you have but a bad opinion of the judges, if you fancy them ignorant to such a degree as not to know that those doctrines are found in the books of Anaxagoras the Clazomenian, who is full of them. And these are the doctrines which the youth are said to learn of Socrates, when there are not unfrequently exhibitions of them at the theatre (price of admission one drachma at the most); and they might cheaply purchase them, and laugh at Socrates if he pretends to father such eccentricities. And so, Meletus, you really think that I do not believe in any god?
Meletus: I swear by Zeus that you believe absolutely in none at all.
Socrates: You are a liar, Meletus, not believed even by yourself. For I cannot help thinking, O men of Athens, that Meletus is reckless and impudent, and that he has written this indictment in a spirit of mere wantonness and youthful bravado. Has he not compounded a riddle, thinking to try me? He said to himself: - I shall see whether this wise Socrates will discover my ingenious contradiction, or whether I shall be able to deceive him and the rest of them. For he certainly does appear to me to contradict himself in the indictment as much as if he said that Socrates is guilty of not believing in the gods, and yet of believing in them - but this surely is a piece of fun.