Let's never forget that Benjamin Franklin was a scientist as well as a statesman, publisher, and philosopher: The Franklin stove and bifocal glasses were just two contraptions he invented, and of course there's that whole experiment with the kite in the thunderstorm. It warms my heart to visit the Franklin Institute in Philadelphia, which pays homage to the quirkiest of our Founding Fathers. At the core of this museum is the Franklin National Memorial, with a 30-ton statue of its namesake and an evocative hands-on gallery on Franklin's inventions and the scientists he inspired. While it looks all stately and neoclassical on the outside, however, this place wouldn't reflect the spirit of Franklin if it didn't have a fascinating clutter of other exhibits that simply encourage kids to putter around.
Hands-on is the watchword at the Franklin Institute; pick up a schedule of the museum staff's frequent daily demonstrations so you won't miss the fun stuff. The collection of science- and technology-oriented exhibits ranges from a gigantic walk-through heart to the Train Factory, where you can play engineer for a 350-ton locomotive, to a Van de Graaff generator that'll make your hair stand on end at the Electricity gallery. Kid Science, on the lower level, uses a dramatic anime-like storyline to teach basic science concepts to children ages 5 to 8. On the third floor, Sir Isaac's Loft demonstrates the principles of Newtonian physics with Rube Goldberg–ian machines, noisemakers, and light shows. The Sports Challenge section was intriguing, looking at the science behind popular sports like surfing and rock climbing, and we couldn't resist the Sky Bike, which you can ride along a 1-inch cable three stories above the atrium floor. The whole museum is all about curiosity, and it's one of the best embodiments of the scientific method you'll ever play in.
In the warmer months, a great high-tech playground sprouts out on the lawn, where young kids can really mess around with science concepts -- the step-on organ is a crowd pleaser, as are the maze and the high-wire tandem bicycle. If your kids like this kind of stuff, you'll probably also want to devote some time to the Please Touch Museum, just a short drive away in Fairmount Park.
Nearest Airport: Philadelphia International.
Where to Stay: $$ Best Western Plus Independence Park Hotel, 235 Chestnut St. (tel. 800/624-2988 or 215/922-4443; www.independenceparkhotel.com). $$$ Rittenhouse Hotel, 210 W. Rittenhouse Sq. (tel. 800/635-1042 or 215/546-9000; www.rittenhousehotel.com).