Gunn High School students will have a chance for an extra half hour of sleep when the school next year moves its morning start time from 7:55 to 8:25 a.m.
Dismissal will move from 3:10 to 3:30 or 3:35 p.m.
News of the change, under consideration by various campus committees since February, came in an email to parents Thursday.
In her "principal's message" to parents, Katya Villalobos cited both pluses and minuses of the change, mentioning extra sleep for students as the No. 1 positive.
"Research demonstrates that 30 to 40 minutes of extra sleep has many advantages, particularly around more focus and less fatigue," Villalobos said.
Teachers and staff also will gain "informal collaboration time" with the change, she said.
The later start time "can also have a positive effect on traffic along the Arastradero Road corridor," she said.
Downsides include a later start time for athletic practices and possible impacts on students with after-school jobs or other obligations.
"We appreciate that a later dismissal will have an effect, and we will work with students to find positive solutions," Villalobos said, adding that the new schedule will be evaluated on an ongoing basis.
Palo Alto High School last fall moved its morning start time from 7:50 to 8:15 a.m. and simultaneously adopted major changes to the school schedule -- moving from a traditional schedule to a "block" system in which classes meet every other day but for twice as long.