It is 11 minutes after 7 a.m. and Robin Boettcher, a 14-year-old Falls Church High freshman, has barely opened her eyes when up rolls The Real World--big, noisy and yellow--and hisses to a stop beside her.

"Morning, Robin!" cries Fairfax County school bus driver Cindy Farmer, wide awake and pleased to greet her first passenger of the day.

Farmer, 35, is the driver--and resident mother/policewoman--of county school bus No. 145. Hers is one of the 672 buses, 97 percent of which are driven by women, that open the eyes of 81,000 bus-riding county students Monday through Friday. She is part of one of the largest school bus systems in the nation and the largest in the Washington area (Prince George's County is second with 670 buses).

Five days a week, nine-and-a-half months a year, Farmer slips out the back door of her county home at 6:55 a.m. and walks 20 paces to the county-owned diesel bus (worth nearly $29,000) parked under a tree. She routinely kicks the tires, checks the oil, tests the safety lights and then heads off for about six to seven hours of work scattered through the day, all for a biweekly paycheck of about $500.

It's a routine that's varied little in the 15 years she's been driving buses. And if her 16-year-old daughter at nearby Falls Church High goes to college, Farmer expects to be driving a bus five, six, seven years hence.

"It's a good part-time job," she says. "I like the freedom of being my own boss and I like working outside."

Farmer is fairly representative of school bus drivers, says Georgia Kivett, a school bus route supervisor. Most are married women in their early to mid-30s, and have children. "It's an ideal job for mothers," she says.

Most of the work is concentrated in the early morning and mid-afternoon so they can spend part of the day at home. Those with pre-kindergarten children are allowed to take them on the route.

"They don't really work for the salary which ranges from $4.28 to $7.50 an hour, depending on length of employment because they can earn more in a supermarket," Kivett says.

Cindy Farmer's reasons for becoming a bus driver are typical. "I was 19 and I wanted to have a job where I wasn't away too long from my baby," she says. But as the years went by, Farmer kept driving because she enjoyed working with the children.

Her route begins about 7 a.m. in the Mill Creek Park section of Fairfax, near the intersection of the Beltway and Rte. 236, where she picks up Robin. Farmer then snakes through the shaded streets, picking up 25 to 30 students she drops off at Falls Church High School, just inside the Beltway off Rte. 50. The entire run takes about a half hour.

Then she heads down Rte. 50 toward Washington, picks up another 30 or so students and deposits them at J.G. Whittier Intermediate School near Rte. 7 and Rte. 50. By 11:30, she has delivered about 30 more children from the Walnut Hill section of Fairfax at Timber Lane Elementary just off Lee Highway, stopped for breakfast and shuttled students among J.E.B. Stuart, Falls Church and Woodson High Schools. She repeats the routes, with some variations, in the afternoon, calling it a day about 5 p.m.

"The first day I got my license, I was put on a bus as a substitute," she recalls. "I was scared to death. I was only a year older than the kids I was giving rides to.

"The kids directed me, because I didn't know where I was going. They did the standard thing, what they do to all substitutes: they made me drive them right to their doors. They took me down to a cul de sac and it took me 10 minutes to turn the bus around when they got out. And they laughed all the time."

Over the years, Farmer has realized she's had a rare chance to watch the ways of children. "The 7th and 8th grade girls, for instance, go through this period where they shriek," she says, shivering. "And the kindergartners often fall asleep and I'll get home and check the bus and here's some little guy sound asleep in the back.

"Then, the intermediate boys in spring go into rutting season, calling each other names, pushing each other, and then love breaks out and the boys walk the girls to the buses for long, passionate goodbyes. That's about the same time the braces come off the girls' teeth."

She knows drivers who see their work only as a job, "Some won't even put on their own snow chains!" And she knows children who leave for school after their parents go to work and return to empty homes.

"You know, it's sad when you see first graders with a key around their necks," she says. "They get on the bus and they're so full of what they've done. They show me their pictures and you know when they get home there won't be anyone there. And when their parents get home, the kids will be run down and watching television.

"But I see enough good things to make it enjoyable. And I like to have fun, too," she says. One Halloween she dressed up as a black cat and the bus broke down near Seven Corners. Before she could get out to examine the steaming engine, a fire truck was on the scene, and it was an embarrassed Cindy Farmer who walked across Rte. 50 to phone in the breakdown to her superiors.

Farmer, who has never had an accident with children on board, nor had a child injured on her bus, says, "My favorite story, though, is when a friend of mine dropped off some high school students and looked outside to see them carrying away her rear seat!"