Part of understanding this case is understand the time in which the case was held. This time being 399 B.C., a time in which Athens was a free democratic city, a town that prided itself at the time on the fact that its citizens had much freedom, particularly freedom of speech. Socrates believed that only people who were educated should rule the people, which meant that people were not capable of government participation unless they had the proper knowledge to do so effectively.
The charge of corrupting the youth originated because the people felt that Socrates teachings had led to the many uprisings by his students. Keep in mind that Socrates had backed none of these uprising that occurred nor did they originate due to any action by him. Socrates supposedly had the right to freedom of speech but now somehow was on trial for doing just that. This trial, I feel, is more of a convenience for Athens than a civil right. Socrates students have disturbed Athens and there is no law being broken.
Socrates did not corrupt the youth. Socrates spread his ideas and teachings to the youths, which is perfectly legal. Every man is essentially his own person and Socrates was now being put on trial for the actions of other people, which is completely unjust. Its easy to see that this charge is a bogus creation of three men trying to make life a little easier around Athens. I am not buying into it and that is why for the charge of corrupting the youth Socrates is not guilty.
What his followers learned from him above all else is to do two things. They learned to scrutinize, and they learned to be skeptical. It was not that they mindlessly adopted a motto like "trust no one over