Start and end times for the day will be different at nearly a quarter of Toronto public schools this September.

The Toronto District School Board says staggered days at 131 schools will help it to plan bus routes more efficiently, in turn saving it some $2.5 million throughout the academic year.

The full list of schools that will be affected can be found here.

"We understand that this may be a change to your family's routine," the board said in a letter sent out to families this week.

"However, if we did not reduce transportation costs by staggering school start and end times, we would have to reduce other services and supports to students that would have more direct and negative impact on classroom teaching."

The changes, first approved last June as part of the 2019 budget, will remove about 55 buses from student transportation routes, the board added.

Students will continue to be supervised for 15 minutes before the morning bell and 15 minutes after the afternoon bell.

TDSB will be holding in-person sessions in Scarborough, Etobicoke and North York to provide additional information to parents and guardians.