For folks at Seattle Public Schools, the school year begins on Sept. 7th (Calendar). Bellevue Schools begin on Sept. 1st (Calendar). Mercer Island begins school on August 29th. And for folks at private schools, here are a few more dates: Seattle Prep – Aug. 26, Lakeside – week of Aug. 29th (depending on grade), Bellevue Christian – Aug. 30th. Enjoy your summer!!