I recently attended the Vans RV assembly workshop in Frederick MD. While I know my way around tools and basic metal working, my experience is centered on cars rather than airplanes.
I was genuinely impressed with the workshop and would recommend it to anyone with an interest in building an airplane.
We started off with a slide deck stepping us through descriptions of the materials, tools, assembly tips & tricks etc. Oh yeah, and rivets. It could be said that at it's core this a course about how to rivet a Vans airplane together. This may sound a bit dry (I found it pretty interesting, though I get excited flipping through tool catalogs), but it goes fairly quickly. Note that you receive a printed manual that covers the material as well -- great for future reference.
There were two projects that we spent the majority of both days working on. The first is a very basic project, attaching two bits of aluminum and a length of aluminum angle. The intent here is to get you warmed up with preparing the pieces (countersinking holes, deburring, etc) and the riveting them together. That's right, before lunch on the first day you have tools in hand and you're setting rivets! The next project is assembly of a control surface. It's a small enough project to complete during the workshop, but is also challenging enough that I believe it gives a valid example of what you would be getting into.
I was appreciative of and impressed by the EAA members running the workshop. They were constantly circulating and offering assistance when needed. Having access to their decades of cumulative experience was great. Even if you have related experience, the access to this resource makes a compelling case for attending this workshop.