Since there's nothing more forlorn than a misfit toy, Maryland Science Center wants to help parents shop for the right toy this year.

The science center at Baltimore's Inner Harbor will be holding a Toy Festival starting the day after Thanksgiving. In keeping with the museum's hands-on theme, these exhibits can be played with. The toys will be grouped according to children's ages, with the developmental stages theorized by psychologist Jean Piaget as guidelines.

If the kids see something they can't live without, most of the toys can be purchased in the museum store, where prices range from 50 cents to $200. Anyone who wants to return without the kids to purchase something -- Santa's helpers and all that -- will be issued a shopper's pass.

Most of the playthings have educational value.The Happy Pumper, for example, is a tractor designed to prepare the kid for energy shortages of the future -- teaching him to pump his own gas, not in tires and propel the tractor with his own feet, if necessary, Electronic toys include a basketball game watch and something called Shuttle Voyage (It's a game! It's a clock! It's a calculator!)

The favorite toy of public affairs coordinator Kristan Leatherman is a teddy bear that crrons, What will happen when more than one kid goes for the same toy is what happens in any nursey school: "The kids will kind of work it out themselves," says Leatherman. "The bully gets the teddy bear."

Enough stuffed animals have been donated to the museum to fill an ark -- monkeyts, penguins and a great gray whale stuck to its Velcro-studded back.

But we're not supposed to call them stuffed animals ant more, says diector of exhibits and facilities Dennis Zembower. "We call them transitional love objects," he says, smiling. It's the euphemism preferred by some toy manufacturers. "Ww have 200 toys here and 100 are transitional love objects," he says.

While the kids are playing, the adults can amuse themselves with electronic games or read up on toy facts such as these: Everyn year, the toy industry produces more than 150 million cars, 2 billion crayons and $40 billion in play money. Mattel is the world's largest manufacturer of women's wear -- over 20 million Barbie-doll costumes a year. The Appollo 8 astronauts went to the moon with Silly Putty.

In display cases, older toys can be seen but not touched: Such lofty personages as the orginal Campbell's Soup kid, Madame Akexander's Scarlett O'Hara and an antique doll with real human hair, are exhibited along with collections of wooden and steam toys. Nearby will be two tents that make up a traveling exhibit called The Toy Connection; the indoor tents are filled with blocks and other toys that have a build-and-design theme.

When the toy season is over, and the exhibit closes, what will the Maryland Science Center do with all the toys? "We'll box them up and save them for next year," says Zembower, "if there's anything left of them."