Laura Brown isn't on the payroll of Discovery Communications Inc. Nor does she get sales commissions from it. But she could be Discovery's secret weapon in the cable programmer's quest to expand into the education business.

Last year, Brown, a media specialist for Paint Branch High School in Burtonsville, signed up for unitedstreaming, Silver Spring-based Discovery's subscription-based, Internet-delivered video streaming application. Through unitedstreaming, teachers and students can view video clips that range in length from 30 seconds to 20 minutes and cover subjects from cell division to sexually transmitted diseases. The clips are categorized by state education standards and are searchable.

Brown was so impressed with unitedstreaming's offerings, she trained more than 200 teachers and students at her school to use it. She also touted the product at a professional conference and in library journal articles. "I can't say enough good things" about unitedstreaming, she said in a telephone interview.

Internet video streaming has advantages over traditional formats, Brown said. "It's so hard to get science videos. It gets so expensive, then people lose them or bring them back damaged." With unitedstreaming, she said, schools can choose from 20,000 video clips, save them to a hard drive, burn them onto CDs or integrate them into presentations. Through its new subsidiary, United Learning, Discovery also provides training and materials such as pre- and post-viewing exercises and teachers' guides.

Discovery Communications, the global media company that operates 60 networks in more than 160 countries, reaching over 1 billion subscribers, is betting that an army of converts such as Brown will ensure the success of unitedstreaming and the company's new business unit, Discovery Education.

Discovery launched Discovery Education in March, several months after it acquired United Learning, a 50-year-old producer and distributor of educational films and videos based in Evanston, Ill.

For anyone who thought Discovery was abandoning its nerdy roots with made-for-advertiser hits such as "Monster Garage" and "Trading Spaces," the new education division is out to prove that Discovery still knows how to dish out the broccoli.

The education business combines United Learning's offerings with Discovery's existing Discovery Channel School products, which include educational videotapes, CD-ROMs and print materials. Discovery has also participated in Cable in the Classroom, a not-for-profit cable industry initiative to provide programming to students.

Discovery executives stress, however, that the new venture is about making money, not just being good citizens.

The way Donald A. Baer, Discovery Communications' senior executive vice president for strategy and development, laid it out in a recent interview, unitedstreaming takes advantage of existing distribution channels, rising demand and cheap content in the form of Discovery's vast video library.

About 99 percent of the 90,000 schools -- and 92 percent of classrooms -- in the United States are wired for broadband, thanks to education-rate, or "e-rate," legislation passed as part of the Telecommunications Act of 1996.

United Learning signed up 25,000 schools for unitedstreaming. Discovery aims to boost that number to about 80,000. At an average subscription cost of about $1,000 per school -- less than a new set of textbooks -- Discovery is looking at a potential multimillion-dollar revenue stream.

"If you add up the total, it begins to be a pretty big business," Baer said.

Playing a bigger role in the classroom "reinforces brand quality," he added. "The long-term hope is that as households become better wired, we can provide a digital library. . . . Once we deliver in the education field, Discovery will be the brand you can trust and bring into the home."

Discovery Education's future customers, as envisioned by Steve Sidel, executive vice president of Discovery Education, could include "baby boomers who want to study art history or molecular biology but don't want to get a degree."

Before Discovery displaces the Encyclopedia Britannica, however, it has to overcome a number of hurdles. "I can't imagine this will be a big market. It's a good, politically correct move to make. . . . The source of the market is tricky," said John Tinker, head of the media/education group at ThinkEquity Partners, a consulting company. He noted that Discovery Education will have to negotiate deals with thousands of technology coordinators and curriculum review committees.

Discovery is ramping up its sales staff and recently began offering a free trial to one school in every school district that doesn't have unitedstreaming.

Few companies offer applications similar to unitedstreaming, but video streaming is just one of many formats educators can use.

Unitedstreaming is a "supplemental material," said Mark Schneiderman, director of federal education policy for the Software & Information Industry Association, a District-based trade organization with about 100 members in the education market. "Schools have lots of digital textbooks and interactive media to choose from."

He said "there is a lot of evidence" that "today's students . . . need that."

"They're used to a rich multimedia environment at home, then go to school and see things more static," Schneiderman added. "The challenge is getting the education system to be able to change their methods and practices using technology. Schools are slow to change."

Persuading a school district to sign up for unitedstreaming can take as long as two years, said Andy Schaefer, a United Learning sales manager for the Washington area. And even though schools have broadband, they don't always have the bandwidth to accommodate heavy use of video streaming. Discovery has developed the unitedstreaming Network Manager, which allows teachers to schedule overnight downloads and offers a local hosting option for schools to keep the video content on their own servers and not have to rely on Internet bandwidth.

Several local school systems already use unitedstreaming. Arlington was an early adopter, subscribing to unitedstreaming two years ago, Schaefer said. Almost all the other school districts in Northern Virginia have followed suit. The District is conducting a pilot project. Some Montgomery County schools, such as Paint Branch High, already have unitedstreaming, and the county is in talks with Discovery on a district-wide deal.

Schaefer said that all the local school districts that have piloted or subscribed to unitedstreaming have renewed for next year.

Unitedstreaming isn't always an instant hit, especially with established teachers. Video clips "are difficult to transfer to something usable in the classroom," said Robert Vandegrift, who teaches national, state and local government to 10th-graders at Paint Branch.

His colleague, science teacher Myones Blair, who has eight computers in her classroom, said unitedstreaming "seemed like a great idea, but I haven't used it much." She said she tends to rely on other materials.

Baer acknowledged that getting in the classroom door can be tough. "It can be hard to get in many school districts. People get used to what's there. But once you're in, then it becomes much more doable to stay and grow."