I haven't tried the board game Periodic Quest, but it seems to have high reviews. Of course, you can always get the Periodic Table shower curtain on Amazon. Nothing says "I'm a homeschooler" like a Periodic Table shower curtain, now, does it?
Also, for Netflix subscribers, I'd personally recommend America: The Story of Us produced by the History Channel and Liberty's Kids: The Complete Series, both available to Watch Instantly. The former is a twelve-episode live-action reenactment of American History (PG level violence, for the most part). Liberty's Kids (rated TV Y7) is an animated cartoon that used to air on FOX and tells, through 40 24-minute episodes, the story of the Revolution. My kids love it, and have never role played American history so frequently!