Students at Stevenson Middle School, part of the LA school district, wave their arms during a music class.
Citing benefits for students as well as for scheduling, the decision comes five years after the board began moving the start of the school year sooner.
Los Angeles Unified School District (LAUSD), the second largest district in the nation, will gradually bump the start date back by one week in 2017 and another week later in 2018.
"I think we're starting too early right now," board member George McKenna, told The Times.
This year, LAUSD began classes on August 16, following a trend nationwide of schools elongating their school years.
In public schools in Atlanta, Georgia, for example, most students began school on August 3, and in Washington, DC, many started on August 8.
An earlier start to the school year allows classrooms to finish the semester before winter break, as well as gives students more time to study for state exams.
In fact, the decision to start the school year later concerns some individuals in the LAUSD district. The board's student member expressed the fear that less time in school will hurt student success.
"Changing the calendar by three weeks could have a negative impact on so many students," Karen Calderon, an Alexander Hamilton High School senior told The Times. "These three weeks have been incredibly beneficial to me .... In changing the start date I think we're limiting the future."
LAUSD contends that the change will still allow the fall semester to end before winter break, a primary benefit of the early start.