Parents and educators across the United States are searching for new and creative ways to help children learn. Children's museums have become an increasingly popular part of the effort. And these exploration centers are the fastest-growing part of the museum community.

Youngsters who visit the Children's Museum of Manhattan can learn about science, the arts, and just about anything relating to the world around them. On this day, first graders (6-7 years old) are learning about what happens to food after it's eaten.

Seven-year-old Deanna says she enjoyed the science experiment showing how the stomach breaks down food. She and her classmates mixed lemon juice, sugar and water to represent the reactions that take place during digestion, and she explained what she learned. "You have acid in your stomach," said Deanna, adding "it makes the food small."

Some members of the museum's staff are teachers. One of them, Lindsey Smith, says she and her co-workers use different programs to reach students. "There's a lot of emphasis on play and exploration, so usually the programs that we teach are very interactive. They're very fun, so it's taking them out of the school environment where they're focused on tests," she said.

Ms. Smith added that one of the benefits of the museum is that children aren't under stress to meet any standards.

The Director of the Children's Museum of Manhattan, Andrew Ackerman, agrees, says the youth who come to his museum learn through hands-on experiences.

"You can be part of that television production. You can crawl through the human body instead of looking at it in a diorama. We know from learning theory that kids learn in different ways," said Mr. Ackerman. "They don't learn just in one way. So we provide different modes of learning, and it's one of the things that makes children's museums so popular."

In fact, there are already 300 children's museums across the United States, and about 400 around the world. Janet Rice Elman, who heads the international Association of Children's Museums, says that although the first children's museum was created in 1899 in Brooklyn, New York, the bulk of them have sprung up since the 1980s as gathering places for parents and their children.

"Children's museums all believe that play leads to lifelong learning. In fact, we have a vision statement for the association that says that we are about bringing children and families together in a new kind of town square where play inspires learning," said Ms. Elman. Still, each children's museum has its own special emphasis. Some focus on science. Others use history as a learning tool. "While we have similar missions, each one is tailored to its own environment," said Andrew Ackerman of the Children's Museum of Manhattan. "So here in New York, we have a television studio. [New York is] where the television companies are located. We focus on the arts, because it is the art capital of the world. ... So that each [museum] takes on its local personality."

Regardless of the focus of any individual children's museum, Janet Rice Elman says they all share the same mission.

"I think the bottom line about children's museums is that we are about our audience. We are about children. We're not about a particular theme like science the way science museums are; or animals, the way zoos are; or fish the way aquariums are, or art, the way art museums are. We are about kids.

For some people that can be difficult to understand until they walk through our doors and see the interactive hands-on spaces where parents and children are having fun together.

The Association of Children's Museums estimates that about 40 million people will visit children's museums this year in the United States alone.

After watching the first graders perform their experiments about the stomach with intrigue and interest, an observer would not be surprised that the public is acquiring a healthy appetite for this type of learning.