Montgomery County students board their bus before dawn in 2012, shortly after an effort to change high school start times began. (Photo by Susan Biddle) (Susan Biddle/FOR THE WASHINGTON POST)

There’s been only a 20-minute change in high school schedules in Montgomery County, but ­17-year-old Luc Cassagnol says he sleeps longer and is more awake for his first-period calculus class. “A huge improvement,” he said of the new 7:45 a.m. opening bell.

But others are less enthusiastic about the districtwide reset of school hours — the first in more than 20 years — saying that the shift intended to help tired teenagers get more sleep has been tough on younger students and their families.

Especially at the later-starting elementary schools, the change has made already difficult hours worse for some parents, upending child-care arrangements and work schedules and leaving younger children more tired at the end of the school day. Classes now begin at 9:25 a.m. at more than 60 elementary schools in Montgomery.

“I just wonder, for what?” says Mark Matulef, a father of three in Bethesda, questioning how much thought was given to parents trying to balance work and family life. “I don’t think anyone explained how this would be positive for the elementary schools.”

Although the shift at elementary schools is just 10 minutes later in the mornings and 20 minutes later in the afternoons, some families have struggled to adapt. More Montgomery students are going to school-based child care in the morning, which can cost $280 to $350 a month per child.

Montgomery County students board their bus before dawn in 2012, shortly after an effort to change high school start times began. (Photo by Susan Biddle) (Susan Biddle/FOR THE WASHINGTON POST)

Bob Sickels, owner of Kids After Hours, which has child-care operations in 20 Montgomery schools, says his morning enrollment is up nearly 25 percent but his afternoon enrollment has held steady. Similarly, morning enrollment has increased by 13 percent in the 31 Montgomery schools where Bar-T provides child care, said Joe Richardson III, chief executive officer.

Montgomery’s change in school hours started with an online petition in 2012 calling for high school start times of 8:15 a.m. or later. Supporters said that the district’s opening bells — then 7:25 a.m. — were too early, with teens boarding buses in the 6 o’clock hour and falling asleep in class.

They cited research linking sleep deficiencies in adolescents to depression, being overweight and having car crashes, as well as lower academic performance.

The school board voted this year in favor of the 20-minute change, which President Patricia O’Neill described as “a step in the right direction” at a time when the 156,000-student district faced budget shortfalls and could not afford costly approaches.

In Virginia, Fairfax County’s schools also recently shifted schedules, delaying high school openings by 50 minutes, to 8:10 a.m. Middle schools start at 7:30 a.m., and elementary schools continue to open between 8 and 9:20 a.m., although many of their schedules shifted by only five to 10 minutes.

“We tried to keep elementary as close as possible to the current schedules to avoid disruption,” said Sandy Evans (Mason), vice chairman of the Fairfax County School Board.

A month into the school year in Montgomery, there is a wide range of reaction from parents, students and teachers. The new schedule means that start times are 7:45 a.m. at high schools, 8:15 a.m. at middle schools, and 9 or 9:25 a.m. at elementary schools. Hours are staggered so that each school bus can be used for multiple runs.

Eric Guerci, the school board’s student member, said he has heard mostly positive comments about the later schedule from middle school and high school students, with a few jokes about how they like it so much, they want more.

Jocelyn Van Dam, 16, a junior at Richard Montgomery High School, said the 20 minutes is disappointing after such a lengthy effort to make a change. “I don’t think it really makes a difference,” she said.

Many parents who supported later start times have welcomed the shift, but many have also said that 20 minutes of extra sleep is not enough, pointing out that the American Academy of Pediatrics recommends a start time of 8:30 a.m. or later. Experts say adolescents need 8 1 /2 to 9 1 /2 hours of sleep a night but find it hard to fall asleep before 11 p.m. because of their natural sleep cycles.

“The science says they need more, but this is a start,” says Mandi Mader, the Montgomery parent who launched the 2012 petition. “Twenty minutes seems to be helping a little bit.”

Mader says she hopes that Montgomery’s school board will continue working on the issue so that high schools can start later and elementary schools earlier.

Angie Melton, a mother of four in Kensington, said she thinks that the change did not achieve what was developmentally appropriate for either group. In her family, it has given minimal relief to her high school student while wearying her fifth-grader, who steps off his bus nearly 40 minutes later than last year, apparently because of more traffic.

“There’s no time anymore to play outside and do something fun after school,” she said, questioning the value of the slight shift. “I would have preferred for them to do nothing and to try to figure out a way to make a real change.”

For Silver Spring parent Julie Grimes, the end of the day also is a problem.

Her fourth-grader, enrolled in a magnet program, climbs off his bus about 4:45 p.m. “By the time he walks home, it’s almost 5 p.m., which is way too late for a 9-year-old,” she said.

Grimes said she doesn’t begrudge high schoolers extra sleep.

“We just don’t think it should be at the expense of the little kids,” she said.

Teachers have voiced “a lot of frustration,” particularly those at later-starting schools, said Tom Israel, executive director of the county teachers’ union. He said he hopes that as the school year progresses, the district will examine the change’s effects on instruction, bus transportation and commuters.

Susan Weinmann, a second-grade teacher in Rockville, said children are exhausted by day’s end at her late-starting school. “It makes it much more difficult to teach anything,” she said. And although dismissal is at 3:50 p.m., the school is often waiting for its last bus 20 minutes later, she said.

Todd Watkins, director of transportation for Montgomery schools, said buses are expected to arrive at schools within 20 minutes of dismissal. “We’ll do whatever it takes to fix it if that’s not the case,” he said.

Watkins said the new schedule has required adjustments in bus pickups because of morning traffic on some high school and middle school routes and afternoon traffic for some elementary school routes. Most problems have been worked out, he said.