To clarify, are you looking for a class to learn more about map and compass use or are you asking about where to learn about the sport of orienteering?
If you're looking to improve your knowledge of map and compass work, we recommend the book Be Expert with Map and Compass, by Björn Kjellström. If you'd like to learn more about the sport of orienteering, please check out this Expert Advice article, Orienteering Basics. It has lots of really good info even if you aren't looking for the sport.
Lastly, please check out this thread, Getting Started with Orienteering, started by @sara, who might be able to provide some insight as to any more resources she may have found. I believe she is also in the Bay Area!
Hopefully this helps!
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