My kids took surf lessons last summer from Surf LA. They had a ball. It was a very upbeat, positive couple hours. We took the lessons at Santa Monica Beach by the Santa Monica Pier. They include wetsuits and the board and some great instruction. I cant remember the exact price but I think it was about $200 for both kids (not each) and it was just the two of them and the instructor, not a big group. I think the lessons were about 2 hours long. It was great. They only took one lesson, which probably wasn't enough to really SURF, but they can both stand up on the board and go a few feet. We plan on doing more lessons this summer.
Here is their phone number: 310-663-2479