Montgomery County students board buses before dawn in 2012, shortly after a petition was created that urged later high school start times. (Susan Biddle/For The Washington Post)

Angie Melton, a mother of four in Kensington, sent out a survey this week on her PTA listserv asking for reactions to this year’s change in school start times in Montgomery County.

In four hours, 52 parents at Garrett Park Elementary responded, many of them answering her survey questions with multiple comments. Melton has not analyzed the results yet, but says one thing is clear: “People have a lot to say.”

Montgomery’s new school hours delay start times to 7:45 a.m. for high schools and 8:15 a.m. for middle schools — a shift of 20 minutes that followed a lengthy effort intended to help teenagers to get more sleep.

Experts say that adolescents, who need 8.5 to 9.5 hours of sleep a night, are biologically wired for later bedtimes and find it hard to fall asleep before 11 p.m. Montgomery’s high school previously started at 7:25 a.m., with many bus pickups in the 6 o’clock hour.

Some supporters laud the change, and others believe it is not enough to really help sleep-deprived teenagers. The American Academy of Pediatrics recommends a start time of 8:30 a.m. or later.

A month after the start of school, much of the concern about the new schedule has come from the latest-starting schools, at the elementary level, where school hours were delayed by 10 minutes in the mornings and 20 minutes in the afternoons, and now go from 9:25 a.m. to 3:50 p.m.

Here are some experiences shared by those affected:

*Marla Roche, a mother of two at Highland View Elementary in Silver Spring, said her school’s new hours have raised new issues of child-care coverage and left her questioning why classes don’t start during hours when young students are most alert. Her children are up two hours or more before school, she said. “That’s their most awake, energetic time of day,” she said. “They play, but they could be learning.”

Like many parents, Roche said she understands the difficulties faced by high school students but thinks there must be a schedule that works better across grades.

*Parent Sudha Srinivasan said she has already noticed an improvement for her high-school-age son who attends Walter Johnson High School in Bethesda.

“The 20 minutes, while it may not seem like a lot, has made a huge difference,” she said, noting that her 12th grader gets more sleep and seems less stressed. His major regret, she said, is that, with graduation in the spring, he only has a year of the new schedule.

“He loves it,” she said.

*At Winston Churchill High School in Potomac, Zack Schoone, 16, a junior, said some students wonder about the value of a 20-minute change, but he likes it. Even though he gets up at the same hour, he feels more rested and less rushed with the extra time. “I feel more prepared for school,” he said. “Mentally, I feel more awake.”

*Krista DiBartolomeo, a music teacher at Wayside Elementary School in Potomac, said she hopes the schedule changes will be reconsidered. Her students are more tired, she said, especially during the last 90 minutes of the school day.

DiBartolomeo said her afternoon commute of 35 to 40 minutes also has grown to about an hour. “The traffic is a lot heavier, leaving later,” she said. One effect: She will no longer offer music show rehearsals in the afternoons, only the mornings.

The change is not working, she said.

*Janelle Ryan, an English teacher at Walter Johnson High, said teens have told her that the change in school hours has not made a difference.

But in her own family, the shift has meant that her fourth grader spends more time in child care and that she and her husband, also a teacher, spend more time at work and in traffic. Even though the school day starts 20 minutes later, the couple must leave at the same time for work, she said.

“I think people would be surprised to know how much a 20-minute change can shake up a family’s life,” she said.