One child is pushing a model train around a track. Another plays peek-a-boo with her mother. A boy stacks cardboard bricks into a tower and hurls himself against them, laughing as they tumble.

Outwardly, there's nothing very remarkable about this large room. But the people who designed and staff it believe the very undramatic things happening here can help strengthen families in an age when they seem to be under ever-increasing stresses.

The room is called Playspace, and it's an unconventional section of the Boston Children's Museum, where, as a sign at the entrance says, the children are the exhibit. Intended for children under 5, Playspace has a wooden model train set, a castle for climbing, blocks, books and a car just the right size for 3-year-olds, complete with steering wheel, seat belts and a "gas pump."

It is a room where play is important, where kids run and squeal and exhausted parents can collapse on a carpet-covered bench or in a rocking chair, check day-care listings, participate in a sewing group or explore a child-care lending library. Parents cannot leave their children in Playspace alone: The point is to bring parents and children together, not separate them.

As more than just a place to play and more than just a rest stop, Playspace has helped shape and now reflects the Boston Museum's philosophy of what a museum -- and by extension other public places -- can and should provide for parents and children.

"We need to think of a family as beginning when the child is born and not when the child becomes socially acceptable," says Jeri Robinson, director of the Museum's Early Childhood Project and developer of Playspace. About 250 kids pass through Playspace on an average day; the room, the first of its kind in the country, has been copied in other museums, an airport and a women's prison.

"Places have to understand that young children come with their own sense of the world and they have to really think about that in their planning," says Robinson, who has a masters in early childhood education. "They can't just say, 'Yes, we want them,' and then frown because they come with their strollers."

Playspace started, says Robinson, "when we set up a fiberglass playpen near a preschool exhibit so parents could put their babies there and get involved in the exhibit." Instead, "everyone watched the babies."

"We were listening to what they were asking each other and found that parents at that time really knew very little about normal childhood development. That turned into the question of what happens to a family with young children going anywhere, and the whole issue became looking at what was happening to these young kids.

"They were often carried in backpacks and they were seen as baggage. You carried the coats and the lunch and the baby and if the baby got tired and got fussy, you left."

This combination of concerns -- the need for information, parents' frustration over going places with their babies and the general lack of consideration for families with young children -- led to the birth of Playspace. In the five years since it was created, museum administrators, teachers and psychologists have begun to see Playspace as the answer to other needs as well.

"What's important to understand here is what's happening to families in our country," says Urie Bronfenbrenner, professor of human development, family studies and psychology at Cornell University, who spoke at a conference on "Family Places in Public Spaces" sponsored by the museum last year.

"The kinds of supports families need are eroding in our nation. But what's happening here at the museum is an exception that's a silver lining. And as a model it goes much further than the specific things it's doing."

Robinson and Bronfenbrenner say the fear of child snatching has contributed to Playspace's success. Like other public places, the Children's Museum has had to adjust to the threat of kidnaping. Playspace is considered a kind of haven, where staffers keep track of the children and guards maintain surveillance at the door. But primarily perhaps, Playspace offers parents -- and children -- the opportunity to meet.

"Much more of this used to be part of community life," says Bronfenbrenner. "There were a lot more activities in which both kids and adults took part. You watched parents in their work. They talked to you. You had contact with adults other than your parents."

Playspace also has responded to other current concerns, including child abuse and the "superbaby" phenomenon.

"We do a lot of trying to dispell the fears of 'superbaby' issues," says Robinson, who sees parents' desire to speed their children's development as a symptom of increasing competition.

"People feel that the places out there are going to be fewer: 'If my kid is better prepared now, maybe that'll be a ticket into Harvard later and then he can get a job.' We say, 'We're not going to teach your kid to read by 18 months. A lot of studies have shown that the child who reads at 3 doesn't read any better than anyone else at 9.'

"We get a lot of calls, 'You know, there's nothing in this city for 18-month-olds to do.' We didn't know they needed a social calendar. Your child needs you to play with him."

The entire staff also watches throughout the museum for what Robinson calls "the difference between child abuse and parenting under stress." Parenting under stress is what a frazzled mother experiences on a rainy day when the infant is hungry and the toddler starts to kick and scream for the sixth time in two hours.

Tantrums, says Robinson, are "torture" for parents; they don't know whether to be embarrassed or furious. "We tell them, 'We've seen this 150,000 times here,' or 'That's not the best tantrum I've seen today,' to help her understand that she isn't the first, nor will she probably be the last this happened to.

"And yes, she is absolutely right to be angry and upset and disappointed, but developmentally it is exactly where the kid is going to be. And there is no magic cure to make it stop. What is going to help most is her own attitude about it."

Bronfenbrenner believes Americans in particular have trouble with children. "We become human as a result of contact with the older generation, and if that link is not there we become uncivilized.

"In every other country people say, 'Oh look, a child. Can we help out? Is there anything we can do?' They start conversations. Here, we go, 'Every man for himself,' and we sort of think everyone's a man regardless of their age or sex.

"We think of ourselves as a child-centered society, but in point of fact we are not, and we pay a price."