I don't know what you consider affordable, but the Crucible offers half-day arts classes open to kids 8 and up. My daughter has done multiple week-long summer camps there, mostly leatherworking, and it seems to be in line with the way you describe the carpentry class.
The Crucible in Oakland has all kinds of cool classes in things like glass-blowing and metal-working. It’s a short walk from West Oakland BART, so she could probably get herself there and back.
A few years ago I took some woodworking classes at The Crucible. I met some really interesting people, learned some new skills, and got a beautiful table and jewelry box out of it. The Crucible is expensive, but Laney has a well respected woodworking program (although I don't know how hard it is to get into). Good luck!
Archived Q&A and Reviews
Re: Something new for 11-year-old this summer
I can respond re: The Crucible. My kids went there for two weeks last summer, and they said it was one of their favorite camps ever (at least partly because they served extra snacks!). Seemed well run, and they certainly learned quite a bit and really enjoyed themselves. My son recently retrofitted the robot he made there to do something else, so I was happy to see the wheels still turning in his mind. My only issue was the cost. It is one of the priciest options around here. They mentioned after the fact that about half the kids attended either free or on a significant scholarship, which in theory I think is great. However, I have no doubt that it was the dollars of the full price families that contributed to these ''scholarships'' but with no associated tax deduction. If I have to make a charitable contribution, then at least let me save on taxes. As I write this I realize I sound like a shrew, but at $1000/week for my two kids- it was quite an expense, and one we really had to stretch for. anon
Re: Adult jewelry-making classes
Look into the Crucible in Oakland (www.thecrucible.org), near the West Oakland BART Station. I've taken two silversmithing classes there, and they're great. Their focus is industrial arts (including welding, casing, torch-cutting, pottery, glass-work, etc.). The 10-week classes aren't cheap but well worth it. Carrie