Known as the "man who saved Christmas," Salem's A. C. Gilbert may not be familiar to most people, but the toy he invented, the Erector Set, certainly is. Erector Sets have inspired generations of budding engineers, and it was during World War I that Gilbert saved Christmas. It seems Congress wanted to turn his toy factory into a munitions factory, but after taking Erector Sets to Congress, he convinced the legislators that America needed to prime its next generation of inventors just as much as it needed to prime its war machine. Here, in two Queen Anne Victorian homes, a few other small historic buildings, and a half-acre outdoor play/recreation center, the 21st century's inventors can let loose their own creative energies. Among the many interactive exhibits here are plenty of Erector Set constructions and a bubble room.