What would be a good English course for a 17 year old to take over the summer in Orange County, California area?

I need to add, what kind of course should I be looking for someone who has an elementary knowledge of English? how to avoid English schools that are only interested to take you money?
Usually, the student will be put in a class with others of similar level regardless of which course you choose. Which course you choose depends on what you want him to learn (subject matter) and how many hours per day you wish him to study.

It is difficult to know how to choose a good school just by looking at their website. The best way is to talk to students who've already been there. Also of course make sure the school is accredited by a party that doesn't have a conflict of interest.

Good luck!