Blackcat, my kids don't really like history, so this suggestion is third-hand, but have you looked into things like history bee, and national history day? I know kids around here really like both. I'm not sure of the target ages for history day, but the bee has team and individual things for several age ranges. It sounds like it might be more factoid- oriented (aren't most bees?) but it might be a way to connect with other kids, teachers, resources, etc. If I remember correctly, the history day is more of an in-depth research/writing activity about a chosen topic- might be a good way to channel or focus some of that intensity.
