Moneek Pines-Elliott saw the light leaking from under her son Jalil's bedroom door way past bedtime. It was early September; Jalil and his twin brother, Jamil, had just started ninth grade at Germantown Friends School.

Pines-Elliott found her son perched on his bed, laptop open. "I'm doing homework," he told her. "I'm almost done." Pines-Elliott checked the time: nearly midnight.

"I was thinking: Oh, my, I hope this isn't going to be habitual. I knew GFS was going to be more challenging, but I'd never thought about the homework. I said to my husband, 'Is that healthy?' "

Pines-Elliott isn't the only one who's wondering. In high-performing schools across the nation, including several in the Philadelphia area, educators and parents are asking the hard questions about homework: Is it meaningful? Is it effective? And how much is too much?

In Ridgewood, N.J., an affluent community in Bergen County, 12 miles from Manhattan, where 95 percent of high school graduates attend a two- or four-year college, students just enjoyed a homework-free winter break, the result of a policy launched in 2010.

In South Jersey's Galloway School District, the board approved new homework guidelines last summer; they call for homework to be "meaningful and manageable" and prohibit written assignments from being due on Mondays or the day after a holiday.

Lower Merion School District, too, recently took the red pen to its homework policy. The new version calls for no more than 10 minutes of homework per grade level each night - that is, 20 minutes for second graders and a maximum of two hours for high school seniors (though the limit doesn't apply to honors, Advanced Placement, or International Baccalaureate classes).

"There needs to be a revolution in homework," says Annie Murphy Paul, author of the forthcoming Brilliant: The New Science of Smart. "Too much homework can produce stress and lack of sleep, and can interfere with students' motivation and love of learning."

In some schools, the revolution is already under way. At Wissahickon Charter, the Germantown K-8 school where Jamil and Jalil graduated in June and where their father, Jamal Elliott, is co-CEO, a similar philosophy prevails. "We want to educate the whole child," says Kate O'Shea, director of the lower school, and that means limiting homework, especially in grades K-5. All students at WCS are required to read each day, but "sometimes," says O'Shea, "I wonder about the value of other homework - if it doesn't just become a thing kids dread."

Several books, including The End of Homework, The Case Against Homework, and The Homework Myth, have argued that homework infringes on other activities, creates tension between parents and kids, and drains the zest and creativity from learning.

And families, especially those whose children attend academically rigorous schools, grapple daily with the jammed window of time between hockey practice, cello lessons, religious school, play rehearsals, and bed.

When Jamil and Jalil were in middle school, the family always sat down to dinner together at the kitchen table. Now, Pines-Elliott sometimes brings food to the dining room, where the boys are toiling away with their laptops and books, and lets them have a "working dinner." On weekdays, says Jamil, "we never really get a chance to relax."

A more public conversation about homework at schools around the country was jump-started in 2010 when a documentary, Race to Nowhere, premiered. The film offers a grim picture of students crushed by the demands of performance-based, test-driven, high-pressure schools. A follow-up campaign by the filmmakers has drawn 6,000 people nationwide to sign an online "homework pledge," vowing to work toward homework-free weekends and holidays in their schools.

In Lower Merion, a screening of the film prodded parents, teachers, and administrators to examine the research on homework: How much were kids actually doing, and was it doing them any good?

Their findings were mixed. Harris Cooper, professor of psychology and education at Duke University, reviewed dozens of homework studies and concluded that there was no correlation, for elementary students, between homework and achievement. For middle- and high-school students, Cooper found, there is some benefit to homework, but there are diminishing returns after about 90 minutes of homework for middle-school students and 2½ hours for high-schoolers.

Paul, who wrote a New York Times op-ed piece in September about homework, says "how much" isn't the only relevant question to ask about homework. "Good" homework, she says, reflects new research on how we learn best - for instance, through repeated exposure to the same information, through tackling different types of problems on a math worksheet, and through frequent self-quizzing that reinforces memory.

Has the amount of homework really ramped up? A 2004 University of Michigan study of children between ages 6 and 17 showed that time spent on homework had risen 51 percent since 1981. But the kids in the study weren't doing a staggering amount of homework to begin with: just over 2½ hours per week at the study's start, and nearly four hours per week by its conclusion. At top-performing schools, many students report doing that much homework, or more, every night.

Shaina Carroll is one of them. A senior in Harriton High School's demanding International Baccalaureate program, Shaina has nightly homework in calculus, American history, Latin, chemistry, Theory of Knowledge, English, and economics. She is also writing her "extended essay," a 4,000-word paper required of all IB seniors; hers is a statistical analysis of pitching on short rest in major-league baseball, and it's due Friday.

Shaina is proud to say she has never stayed up past 12:30 a.m. on a school night to do homework, and she believes the assignments have deepened her learning, honed her writing, and made her more efficient. "Do I wish I had less homework? Yes," she says. "Do I understand why I have this much homework? Yes."

Shaina's mother, Terri Laufer, thinks the IB program's benefits outweigh its heavy academic load. "She'll come home truly ramped up, saying, 'We had this really interesting discussion in history today.' She's incredibly good about time management. I don't worry that much about Shaina."

Wendy Cramer, on the other hand, worries a lot - not just about her own daughter, a senior at Lower Merion High School, but about the young women she sees in her work at the Renfrew Center, a treatment facility for those with eating disorders. She explains: "I think the pressure comes from the whole culture: the idea that your kid has to do more and more if they're going to get into the best school and get the best job."

Cramer made a deal when her daughter was choosing senior-year classes: only three AP courses, not five, and if she showed signs of distress, such as not eating or sleeping enough, then some activity - most likely, co-captaining the field hockey team - would have to go. "I think we're the only parents in Lower Merion who said, 'Don't take all AP courses. You don't need to push yourself that hard.' "

At some schools, there is no such hand-wringing over homework. Jeffrey Pestrak, chief academic officer of Mastery Charter Schools, says homework is an essential tool for bringing students who lag academically up to speed and for instilling the independent study habits that college will demand. The homework dilemma resonates most in the highest-ranked schools, where parents' expectations, students' ambitions, the demands of accelerated classes, and the pressure to get into "good" colleges swirl into a perfect storm.

And it comes home on the van that, each day, carries fifth-grader Megan Shelton from Julia R. Masterman School back to Northeast Philadelphia.

In elementary school, Megan excelled in her classes and had energy for Chinese school, dance, and violin lessons. This year, homework upstaged all that. "There are times when I say, 'You're exhausted. You're not comprehending. Just go to bed,' " says her mother, Judy Shelton. "Megan will just break down and cry for no reason, she's so stressed and pressured."

Annmarie Marranzini, who teaches eighth- and ninth-grade English at Masterman, has seen signs of stress in her own students: middle-schoolers who are literally falling asleep; seniors buckling under the combined weight of homework, extracurriculars, and college applications.

That's why she spearheaded an effort to screen Race to Nowhere on Thursday at Masterman. The film will be open to the public. "I would love to see weekends or holiday breaks free of homework," says Marranzini. "When you're a nationally ranked school, you think: We're doing it right. But are we? I think we should just question more."

Masterman's principal, Marjorie Neff, agrees. "We have to ask: What's meaningful, what's necessary, what's enhancing? I don't think there's a right or wrong answer about homework. The question is: Are we doing the best for the total kid?"

Anndee Hochman is a journalist and the parent of a Philadelphia public school student. Contact her at aehoch@aol.com.