Every school has a hardy group of super-parents who make it their job to bake the cookies, chaperone the field trips or run off worksheets on the copy machine. But in a few school programs in Prince William County, parent involvement is mandatory, not an option shouldered by a few.

Parents at the Pennington and Porter schools, two specialty schools that draw children from across the county, sign a contract pledging to volunteer at least 10 hours for every child they have enrolled. If they don't, their children may be returned to their base school, although to date that has not happened.

In addition, the county tried requiring parenting classes earlier this year for the families of some children on long-term suspension. The pilot program, paid for with a grant, was so successful that educators are considering offering the classes to parents of students in New Directions, a program at two high schools for students who otherwise would be suspended or expelled.

New Directions administrators will do more than suggest that parents get involved, said Renee Lacey, supervisor of alternative and summer programs. "We say to parents, 'We want you involved, and these are the things you're going to do,' " Lacey said, adding that most parents of a student in trouble will do just about anything to keep the child in school.

The parental contracts and other requirements are "an essential part of Pennington," Principal Joyce Boyd said. The school prefers to have the obligations performed at school during the day, but working parents can perform data entry at home, volunteer on weekends or help with spring beautification -- a well-attended event for stragglers, said Renee DiDuro, Pennington's PTO president.

Encouraging such involvement is a challenge faced by schools across the country.

"People have realized that parents being engaged in the life of a school is an important part of being successful," said Douglas Wood, executive director of the National Academy for Excellent Teaching at Columbia University's Teachers College. A former executive director of the Tennessee State Board of Education, Wood helped create statewide standards that schools must use to promote parental involvement.

There is no punishment for Tennessee parents who choose not to get involved. But the state legislature there debated all sorts of carrot-and-stick approaches, Wood said. Facetiously, one person even suggested jail time for the recalcitrant.

"There's a general sense of urgency and, in some cases, frustration that parents are not as involved as they ought to be," Wood said.

The urgency is backed up by research: In general, involved parents have successful children. At a time when testing is a key measure of performance, administrators are searching for every edge. The federal government is also behind the concept: No Child Left Behind regulations require schools with high percentages of poor children to create parent outreach programs.

That means seeking out parents who don't step forward, said Joyce L. Epstein, director of the Center on School, Family and Community Partnerships, based at Johns Hopkins University. "If this is so important to children and we know that only some parents are involved . . . isn't there a responsibility to create some kind of program that makes the shared responsibility easier?" she asked.

Parent involvement is only one of the things that make Pennington and Porter different from other Prince William schools. They are open to first- through eighth-grade students, who wear uniforms and must adhere to strict behavioral standards. They have proved so successful that lotteries are held to select students.

Molly Bramble, the PTO vice president at Pennington, spent her first year at the school as the parent volunteer coordinator.

"You sign the contract, and you've got to keep your part of the bargain," said Bramble, whose children are in fourth and sixth grades. "What does that show your kids if you don't?"

Two mothers who went -- reluctantly, in one case -- through the county's classes for parents of children under disciplinary measures said the courses turned out to be worthwhile. Both spoke on condition of anonymity so their children could not be identified.

The students, both boys, were on long-term suspension because of conflicts with their teachers. Normally, they would be excluded from school services, but in the program, they were allowed to take basic coursework, along with behavior-management classes. Parents attended a separate eight-week parenting seminar, held once a week.

"He thinks a lot more before he reacts, and so do I," one mother said of her son. "If the teachers were required to take this, they would do a lot better in the classroom."

The other mother said she was a little bit angry at the beginning, then learned from the class how to establish clear boundaries for her son and consequences when he overstepped them. "If you want your child to succeed, you've got to do what you can to keep them in the system," she said.

Epstein said she believes that parent outreach programs should be a standard part of school programs, just like reading instruction. "People have begun to see this as a part of good school organization, not just 'extra' stuff," she said.

Renee DiDuro, PTO president at Pennington School, helps Elizabeth Bramble and Lucas Brock with homework as part of her volunteer commitment.Parent volunteer Margaret Simmons hangs classwork in a hallway at Pennington, a Prince William school that has volunteer contracts with parents.Pennington volunteer Michelle Bennett works with Miranda Darden, 7. Parents agree to volunteer 10 hours for each child they have enrolled.