Bay Area Discovery Museum, Sausalito, California; 415-487-4398
Dive into an imaginary underwater world made from nearly 200,000 Legos. As ocean explorers, kids ages 3 to 12 play scientists in a submarine, create sea creatures and underwater transports, and hang out with the world's largest Lego octopus, built by hundreds of Bay Area children.
Canadian Children's Museum, Hull, Quebec; 819-776-7001
In this fictional town, kids ages 5 to 12 learn about the simple tools -- such as levers, pulleys, and wheels -- that make our day-to-day lives easier. Activities include testing playground equipment, playing foreman at a construction site, and working on a dock as a clam fisherman.
The Children's Museum of Houston, Houston, Texas; 713-522-1138
Your children will learn geography without even realizing it as they pilot kiddie-size cars, trains, trucks, and boats to destinations all over a virtual globe. They'll also have a ball creating an earthquake, transporting grain from farm to market, building a bridge, and playing search-and-rescue in the mountains.
The Children's Museum of Indianapolis, Indianapolis, Indiana; 317-334-3322
In this creative exhibit, kids of all ages get to slip on shoes from more than 40 countries, including reindeer boots from Finland, rice-straw sandals from Korea, and firefighter boots from the United States. At the Global Factory, they can weave their own shoes, make a moccasin, or assemble a Chuck Taylor Converse sneaker.
The Children's Museum of Memphis, Memphis, Tennessee; 901-458-2678
Send your little explorers back to the Middle Ages. On this journey, based on David Macaulay's popular book Castle, they'll see Lord Kevin's great hall, buttery, and stable. They'll also enjoy dressing up as kings, queens, or knights, and learning how to protect the castle from intruders.
Minnesota Children's Museum, St. Paul, Minnesota; 651-225-6001
Children enter the colorful world of the big top to discover what it feels like to be part of a circus family. After learning how to walk a tightrope, act like a clown, swing on a trapeze, juggle, ride a unicycle, and train elephants, kids ages 5 to 12 hit the ring themselves and put on the greatest show on earth.
Brooklyn Children's Museum, Brooklyn, New York; 718-735-4400
In honor of the 30th anniversary of the TV series, visitors take a tour through the show's most famous hangouts, such as the brownstone and the Sesame Mucho Rainbow Bodega. Call ahead to find out when Elmo and Cookie Monster are scheduled to appear live.
Fort Worth Children's Museum, Fort Worth, Texas; 817-255-9300
Children of all ages practice teamwork, strategy, and sportsmanship as they challenge one another to leapfrog, hopscotch, checkers, pig-in-a-pen, tic-tac-toe, dominoes, and more. They can also try their hand at international children's games such as mancala, an ancient African game of strategy.
Chicago Children's Museum, Chicago, Illinois; 312-527-1000
Gumby, the popular green clay figure whose escapades have entertained generations of children, is the spokesman for the Library of Congress's Center for the Book. In this exhibit, children make up stories, explore prehistoric places, and learn about Claymation.