FREMONT — Classes in the city district may start and end 25 minutes later for high school students, and 10 minutes later for junior high students, possibly starting this fall.

Administrators are working out details to determine if it's feasible for the new schedule to take effect as early as September, but a majority of school board members indicated last week they would like to see the change implemented as quickly as possible.

The decision follows a recent community survey that asked respondents whether the school day should be pushed back at secondary schools. About three-quarters of respondents agreed that high schools, and in some instances, junior high school, should start later, though there were disagreements as to the preferred start time.

The survey, conducted over six weeks and filled out by 2,251 people, included responses from parents, students, district employees and community members.

The most popular choice, and the one that the board went with, will have high school students in class 8 a.m. to 3 p.m. and junior high students in their seats from 8:15 a.m. to 2:25 p.m. Elementary schools, which on average start at 8:30 a.m. and end at 2:50 p.m., will remain on the same schedule as this year.

Under this scenario, parents dropping their children off at multiple campuses will have 15 minutes between when the junior high and elementary school bells ring to get their kids to class on time — 10 minutes less than under this year's schedules. Similarly, those dropping their kids off at a high school would have 15 minutes to then get to a junior high campus to drop off their younger child — 15 minutes less than now.

Trustees said they realize there are details to be worked out, but they believe pushing back the school day is in students' best interest.

Studies have linked added sleep with improved health and academic success. And, in light of massive budget cuts next year, "why not take the opportunity to try to do something nice for our students?" board President Lara York asked.

"All the indicators are pointing to that if we do this, it will help them overall. I don't see the downside," she said.

Studies have shown that teens naturally fall asleep and wake later than younger children. Advocates of a later start time say pushing back the school day at the secondary levels would result in fewer tardy students, and more attentive students.

Others question whether teens would get more sleep or take advantage of the schedule change by going to bed later. Opponents of a schedule change also worry that later school days would interfere with the schedules of students who have after-school jobs or who play sports.

In addition to gauging community desires about the start and end times of school, the recent Fremont survey found that only 5 percent of local high school students sleep more than eight hours per school night. In fact, more than half sleep six hours or less, while some medical studies suggest that teens should be getting nine hours of shut-eyes per night.

Fifty percent of high-schoolers also spend four or more hours on homework each day, according to survey results.

Contact Linh Tat at 510-353-7010. Follow her at Twitter.com/Linh_Tat.