Keeping their kids off the streets and on a safe, supervised motorcycle race course is the aim of parents in the Scholastic Moto-Cross Club of Fairfax. Now in its second year, the club has a meet for high school and younger students Saturday at White Oak Moto-Cross Park near Fredericksburg, Va.

"Many kids who are mechanically inclined aren't interested in the usual high school sports," points out Charles Sanders who, with his wife Elizabeth, are among the dozen or so club members. "They like competition and machines. Moto-cross is very competitive. It demands riders be in good physical condition, and it's as safe as any sport under supervised conditions."

A moto-cross is run over a track, usually a half-mile or less, laid out in open fields with hills, sharp corners, jumps and perhaps a water hole. Even the pros seldom race in more than 20-minute "motos." The kids get in a half-hour or longer of practice and racing during their meets, Sanders said.

Competitors must be students. "We had one 8-year-old race last year," Sanders recalled. "His parents tied a ribbon to his helmet so they could spot him. When he crossed the finish line after a race, mom grabbed him and dad grabbed the bike."

Last season, 190 youngsters from 88 schools raced in Scholastic meets. "We have classes for every type of motorcycle for girls and for first-timers," Sanders said.

Safe? "Well, we've run more than 100 separate races and the only injury has been a dislocated finger which the rider popped back into place before anyone could help her," Sanders said.

Few of the adult Scholastic members are motorcyclists, Sanders said, a rider since 1950. His wife rides and their two sons race. The children of other active members, such as the Dave Smiths, the Bill Fletchers and Billy and Dr. Elizabeth Moore, race.

School officials have been helpful, too, Sanders added. Principal bob Russell of Robinson and vice principal Bob Kennedy of Edison High have encouraged the sport and have clubs in their schools.

"In California, some schools give a sports letter for motorcycling," Sanders said. "Our idea is simply to have the kids compete against riders their own age and do it safely."

Sanders admits Scholastic has some money problems. "Our dues are only $6 a year and entry fees $2-$3. From that, we must rent the track, get insurance, pay for race equipment and, of course, buy trophies," he explained. "We're still on a race-to-race basis but we expect a good year."

As motor sports go, moto-crossing is relatively inexpensive. According to Sanders, almost any motorcycle may be used if all glass and protruding metal is removed. Every machine is inspected before a race. Riders must have a helmet, goggles, gloves, long-sleeved shirt, heavy pants and boots that lace above the ankles.

There is a club meeting Tuesday night at Edison High.