Airventure Workshops
The Airventure workshops, in the forum area, are designed to give folks a taste of different aspects of building. These workshops are only a few hours long, for instance I volunteer at the sheetmetal workshop which is put on at 8:30 and 1:00 every day. There is a one-hour lecture and 2-hour handson project (10 rivets total).
The SportAir workshops are much more indepth and span two weekend days (and sometimes a bonus evening event). The one I attended assembled a flap segment.
I was a slow learner and did the Oshkosh workshop then the RV Assembly Sportair Workshop, because I had no sheetmetal experience. 8-years later and I still don't have my plane done, but I can tell people whether they have a good rivet vs. bad rivet and how to set up a counter sink cage.
It think the Sportair workshops are well worth the price.