Bay seniors looking for an illuminating experience this summer should check out the classes being offered at the Crucible in Oakland on the art of neon. Learn the techniques involved with fluoresence, neon, LED and plasma. An introductory class,for example, is held on Sunday June 22 and June 29 from 10 am to 6pm. $435. The Crucible is an invaluable resource with classes in everything from Blacksmithing to Fire Performing.