Another way to experience Comic Con is to volunteer. Volunteer sign up is online, usually about 7 months ahead of time. I've volunteered the past two years and have really enjoyed my time. You pledge to spend 2 hours a day doing whatever task you're assigned (you get some choice, so if you can't do something like heavy lifting, don't worry!), in exchange you're granted free admission and a free t-shirt! I had a lot of fun working the check in booth for exhibitors, assembling their swag bags. When our time was done the ladies in charge gave the volunteers their own swag.
Popular panels are very difficult to get in to and require waiting in massive lines. For the Harry Potter panel in 2010, fans were sleeping overnight. Some people once they get into a panel room stay all day. This makes it difficult to attend panels if you're volunteering. But there are lots of other things to do, the exhibit hall is massive, there's always fan meet ups, and smaller panels.
Hope that helps! Comic Con is a ton of fun, especially for teens. And San Diego is one of the best towns in California, definitely worth a trip!