The Upper Floor area is the mezzanine level of the main gallery. "Mezzanine" is just a two-dollar word that means "balcony," more or less. This level (about 1,200 square feet) is devoted to tinkering and other kinds of hands-on, not necessarily historical, exploration. It's very popular. We say it's for kids, but more than a few adults play here, too. Yeah, we're onto that, "I'm just here with my grandkids" bit, fella.