Parents Not Admitted Without Child Guardians

Here's what I've discovered while sightseeing with my 5-year-old: Children's museums are a parental lifesaver. Fortunately, they're everywhere--at least 135 cities have one or more--and they usually offer an absorbing and fun distraction. Unlike the stodgy old museums you and I may have grown up with, where patrons could look but not touch, these institutions invite hands-on participation. From simulated archaeological digs to replicas of log cabins, kids are encouraged to climb over, crawl through, and interact directly with the exhibits.

The hands-on philosophy of today's institutions took root in the 1960s, when a few pioneering curators decided to apply to the museum world the learning theories of 20th century child psychologist Jean Piaget--that children learn by interacting directly with their environment in developmentally appropriate ways. Now, in addition to some 200 existing dedicated museums for children in the U.S. and 100 more in the works, a great many traditional museums have added so-called discovery rooms for kids or hands-on additions to regular exhibits. (Check the tourist office in the city you're visiting for locations or call the Association of Youth Museums in Washington, D.C., 202 466-4144.)

While it's hard to find a children's museum that won't provide an hour or two of entertainment, some are so enthralling that your kids won't want to leave. In many cases, you'll feel the same. One such destination is the Children's Museum of Boston, whose director back in 1962, Michael Spock--son of the baby doctor--was a pioneering curator.

Soon after you and your charges arrive at this four-floor, 31,000-square-foot building, you are greeted by a unique "climbing structure." Hanging between the second and third floors and looking like a wire-mesh cage, it is filled with nooks and crannies kids can climb through. It's enclosed, of course, so no one can fall out. During vacation times and weekends, it's crammed with giggling children.

On the second floor, an area called Under the Dock features a 14-foot fiberglass lobster with claws you can move. The El Mercado del Barrio display replicates a Spanish grocery store. There's also a Native American wigwam and a Japanese home from Kyoto, with a rock garden. Beginning this summer, a Boats Afloat exhibit will use a 28-foot tank with 800 gallons of water. Kids can create boats out of recycled material, then watch the current pull them along. The scene is a replica of the Four-Point Channel in Boston Harbor you can see out the window.

Not all children's museums offer notable attractions for the under-4 set. However, the Boston museum's Playspace, aimed at infants to 4-year-olds, has served as a model for other institutions. Another popular facility with ambitious exhibits aimed at younger kids is the Children's Museum of Manhattan (212 721-1234). The Bridge of Songs, for example, lets little ones walk (or crawl) over a bridge; with every step, they hear a different musical note and see various changing colors.

DOME OF SECRECY. On the other side of the country in San Francisco is the granddaddy of science and technology museums, the 27-year-old Exploratorium. Expect to spend the better part of a day or two investigating its 700 exhibits. The Tactile Dome offers a real adventure, one that could be frightening or fascinating for little ones. It's a pitch-black half-dome that children crawl through, relying on touch. All sojourners are sworn to secrecy about what's inside. Suffice it to say, the dome is equal parts maze and funhouse, where children descend down slides and tunnel through textured rooms. It's such a hit, you have to reserve a spot (415 561-0362).

While other popular exhibits aren't as dramatic, they're still a lot of fun. In the Tornado, you step into an eight-foot-high Plexiglass cylinder with water underneath. It forms a fog that rises into a swirling vortex, much like a tornado. The Shadow Box includes a wall covered with a phosphorescent material; every 90 seconds a light flashes, creating what appears to be a shadow, which is captured on the wall for a minute or two.

From the end of June through January, you can also see Turbulent Landscapes, featuring works by 13 artists who use forces of nature as their creative medium. In the display titled A Single Drop, a water droplet lands in a pool, causing ripples to move across the surface, bounce off the edges, and create elegant patterns as they crisscross each other. It's quite hypnotic.

ANGLING AND ART. The Exploratorium isn't the only children's museum in the region worth a visit. On the site of a former Army base in Sausalito, the Bay Area Discovery Museum contains seven buildings that form a child-size village. In Bay Hall, there's a mock pier and boat with fishing rods and nets you can use to snare plastic fish and crabs. At a mini-Fisherman's Wharf, you weigh and price your catch. You'll also find areas dedicated to art projects, from toy boat construction to jewelry design.

This museum tries hard to offer exhibits that appeal to toddlers as well as 10-year-olds. Consider a special show, Andy Warhol: Myths, Series, and Studio. It will feature six original Warhol prints, plus an area where older kids can do silk screening and smaller ones can do stamping and stenciling.

One place aimed at the littlest set is the Please Touch Museum in Philadelphia, which caters to kids aged 1 to 7. Take an exhibit called Growing Up. It teaches about stages of development and offers a glimpse of childhood in other cultures. A shaky floor simulates the feeling toddlers get when they are first learning to walk. For the under-2 set, Nature's Nursery has a garden motif. Open a little door and see a baby bird; when pressed, buttons on the wall make chirping, buzzing, and other outdoor sounds.

From May through October, visitors get an added bonus: a 25,000-square-foot outdoor exhibit called Science Park. It's divided into 20 sections, including a bubbling volcano, a sundial, and a real eye-opener--the Sky Bike. An experiment with gravity, it's a two-seat bicycle with a pendulum attached, poised on a wire 18 feet off the ground. Oh, yes--you and your child ride on it, too.

A new and improved entry in the hands-on world is the Chicago Children's Museum. Its facilities, located at Navy Pier, are triple the size of its old location. A major attraction is the Inventing Lab. In one section, children create "flying machines" from foam-rubber wings and bodies. Then they crank the gizmos up a 50-foot-high conveyor belt, time the descent, and rejigger their inventions to improve the speed. If you're looking for a lesson in social justice, the Kids' Bridge features an interactive video in which children recount their experiences with prejudice. Visitors also walk through The Prejudice Bus and hear unpleasant epithets hurled their way; once off the bus, they watch a video showing how to handle such situations in real life.

INDY WINNER. In the final analysis, the numero uno of hands-on museums is probably the five-story Children's Museum of Indianapolis. Its latest claim to fame is a show of nearly 100 works by the sculptor Alexander Calder. This will be the first time a children's museum has hosted a fine-arts exhibit of this magnitude. Next door, kids can make their own Calder-like moving objects. Also, on June 8, an ambitious 10-section science exhibit will make its debut.

The rest of the museum is pretty elaborate as well. There's a Victorian-era railway depot, along with a locomotive and caboose you can climb into, a coral reef with a tropical-fish aquarium, a dinosaur dig, and a planetarium--and that's all on level one. Up on level four, Mysteries in History features an archaeological dig with bones, rocks, and other treasures buried under sand. Kids are free to pitch in and uncover what they can. They can also climb in a log cabin, circa 1830, or sit behind the wheel of a car driven in the 1980 Indianapolis 500. Such exhibits please the kids and bring out the child in the adults as well.

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