PBS has created an online neighborhood for preschoolers, the latest of a growing number of subscription-based educational sites.

The service, "PBS Kids Play!" opened this week (pbskidsplay.org) for a free beta trial period. It's designed to let children 3 to 6 play and learn with the help of characters such as Curious George and The Berenstain Bears. Activities will be added every week featuring Bob the Builder, Thomas & Friends and characters from Mister Rogers' Neighborhood.

When the trial ends before spring, the service will cost $9.95 a month or $79 a year. PBS expects some local TV affiliates to offer it at a discount or free to donors.

PBS Kids senior vice president Lesli Rotenberg says charging for online programming is "a new direction that is much more convenient for consumers" than packaged media such as CD-ROMs.

"This is an evolution," she says. "It's a new way to do business. And the public has always been very accepting of PBS being able to take profits from the sale of products and put them back into its media."

Online learning diversions have been available for years, but a new crop of in-depth for-pay services aims to engage children in customized games and activities. "It is where we all thought the Web was eventually going to head," says Jinny Gudmundsen, video game editor for Common Sense Media, an independent nonprofit, and a usatoday.com columnist. "If you want quality, personalized education content, I think you are going to have to pay for it."

Parents can set up accounts for more than one child and limit screen time. Kids use a mouse to move the large on-screen cursor to click on their icons and explore the bold, colorful environment, and they can save favorite activities and games in a virtual backpack. All content is based on national educational standards.