It’s official. Prince George’s parents, mark your calendars.

Schools in Prince George’s County will start one week later for the 2014-15 school year.

The Prince George’s County Board of Education approved the school calendar Tuesday night, and one of the biggest changes is the delayed start.

Last year, Prince George’s schools were among the earliest to open after the summer break in the Washington region, starting classes on Aug. 19.

This year, classes will begin Aug. 26.

The 2014-15 calendar also adds a system-wide orientation day for sixth- and ninth-graders on Aug. 25.

The change in school opening means classes will end later. This year, the last day for students is June 5. The last day for teachers is June 6. In 2015, the last day for students is June 17, and teachers finish up on June 18.

School Board member Peggy Higgins (District 2) did ask Superintendent Kevin M. Maxwell to study whether the later start in the school year has any impact on testing. She noted that the Board approved the earlier start to school in 2005 and, she said, that for the last several years teachers have credited some of the improvements on the Maryland assessment tests to starting school a week earlier.