It's not your imagination - summer is over

It's official. Summer is over.

At least that's the case for many of the school districts that have already had their first day of the school year.

Some school districts in Georgia may be the worst offenders, where the start of the school year has eked back from August to July 31.

Atlanta Public Schools started a day later on August 1. In California, many districts start a couple weeks later. Los Angeles has its first day of school on August 15.

Numerous other school districts begin their semesters weeks before Labor Day, which many consider to be the unofficial end of summer. Changes to move up the start of school have often been made with students in mind.

Washington, DC moved its start day up last year to avoid the "summer brain drain," the period during which students backslide on the mastery of content they had learned the year before.

"It's a new experience, but we are excited because it gives kids more time to engage with the content," Catrina Brown, an English teacher in DC, told The Washington Post last year. This year, DC schools have their first day on August 21.

In other districts, like Los Angeles, an earlier start helped with the flow of the school year.

"I'd say people feel that it's a better way to lay out the school year," Laurie Baccus, an assistant superintendent at Whittier School District, said on Southern California public radio station KPCC last August.

Not all schools have pushed up their start dates. New York City Public Schools - the largest school district in America - still waits until Labor Day for the school year to start. This year, classes begin on September 7.