A proposal to push back high school start times in Fairfax County is making some parents, students and teachers nervous that extra sleep isn't worth the headaches of a scheduling change.

Most Fairfax high schools start at 7:20 a.m. Middle and elementary schools start later.

Under the proposed change, most high schools would start an hour later. Elementary schools would start between 7:50 and 9:25 a.m., and middle schools would start at 9:40 a.m.

One parent group says research shows more sleep makes teenagers healthier and higher performing. But others worry the different start times could force cancellations of extracurricular activities such as swimming, which relies on coordinating schedules with county pools.

School officials plan to hold meetings and conduct surveys to decide on the proposal.