Some Washington area school districts will begin to compete with private tutoring companies this fall, offering after-school instruction to low-performing students with money provided by the federal government.

Under the No Child Left Behind Act, parents have two options if their children are enrolled in high-poverty schools that have not met academic benchmarks for three consecutive years: Their children can transfer to better-performing schools or receive free after-school tutoring, including from private companies.

The two-year-old federal law has been a boon to businesses that sell tutoring services, design exams and consult with school districts desperate to raise test scores. But in offering the tutoring alternative, known as supplemental educational services, the federal government has embarked on an experiment -- inviting the private sector to become more directly involved in the education of public schoolchildren, which has resulted in an uneasy alliance.

"There's a concern that it opens the door to a new power base, if you will, for instruction that traditionally teachers have been the single source of," said Mark Jackson, a senior analyst at Eduventures Inc., a Boston-based educational research firm. "If the doors open to after-school tutoring and support paid for by public funds, then the argument is put on the table that there are alternatives to the dominant market."

In response, a growing number of public school districts across the country are setting up their own tutoring services to vie for the federal dollars.

Starting Oct. 12, for example, students who qualify for free and reduced-priced lunches at nine high-poverty schools in Prince George's County will receive two to three hours of individualized instruction from certified county teachers at least twice a week after school, in some cases on Saturdays. In Montgomery County, students at seven schools will get 90 minutes of instruction twice a week, beginning Nov. 2.

The D.C. public school system already has two in-house tutoring organizations to compete with 25 other certified providers, both for-profit and nonprofit entities, said Tamika Maultsby, the school system's program coordinator for supplemental services. In Virginia, one provider, the Mathematics and Science Center, is operated by a consortium of public systems in the Richmond area, but no individual districts have applied to be state-certified tutoring agencies, said Charles Pyle, a spokesman for the Virginia Department of Education.

"We can do it in a more cost-effective manner," Prince George's schools chief Andre J. Hornsby said recently as he announced the creation of the county's after-school program, known as "A+ Focus."

The No Child Left Behind law requires school districts to spend up to 20 percent of their Title I federal grant money on both the transfer and tutoring options at high-poverty schools. Last year, Prince George's spent about $1,700 on each of the 300 students who received tutoring from outside providers. This year, Hornsby said, about 3,000 students will be eligible for the services.

Montgomery County, too, paid up to $1,700 for each student. Officials said they do not yet know how many will qualify for tutoring this year.

Under the law, parents do not have to enroll their children in school-based programs and can choose from any state-approved tutoring providers.

Supporters of school-based services point to advantages such as the districts being able to use their own certified teachers, who are familiar with the curriculum. "Our program plans on using [Montgomery County public school] teachers, and we know they are high quality," said Joanne Steckler, a principal who spent the summer setting up Montgomery's after-school tutoring program. "The other providers, they're attempting to recruit teachers, but they may or may not be successful."

The private tutoring services "saw this law as an opportunity to come in the door and make some money," said Jack Jennings, director of the Center on Education Policy, an advocacy and research organization based in the District. "Nobody knows yet how good the private providers are."

Skepticism extends to the school-based providers as well. Some critics argue that a school district's inability to effectively run the failing schools in the first place should disqualify it as a viable source of tutors. Others point out that the school systems play a part in monitoring all the tutoring services -- and essentially would be monitoring themselves.

Because federally funded tutoring is just a couple of years old, there is scant evidence that students are performing better as a result of the extra instruction. In a study released last week, researchers with the American Enterprise Institute, a Washington-based think tank, found that many parents were not aware of their options, partly because school districts were not notifying them in a prompt and clear manner.

"Supplemental services are probably the most significant kind of new approach," said Frederick M. Hess, the institute's director of education policy studies. "It's the one that is kind of the most revolutionary departure from what we've done before. Folks are unfamiliar with it, and it's outside their comfort zone."