FAIRFAX COUNTY’S early dismissal of elementary school students on Monday has long been a source of bewilderment. Parents complained about it, and a succession of superintendents tried to eliminate it, to no avail. So hats off to the school officials who finally ended a practice that was a relic of the past and clearly not in the best interest of Fairfax students.

The board of education voted June 26 to end half-day Mondays, approving a calendar change that will add an extra 75 hours of instruction to the school year. The change will go into effect for the upcoming school year. Administrators presented the plan to the board less than a month ago, and the accelerated approval, as The Post’s T. Rees Shapiro reported, sparked some critics to say that it had been rushed into place.

Never mind that the practice has been the object of study and discussion for decades, including a recent committee that found parents overwhelmingly opposed to half-day Mondays. Whatever the onetime usefulness of the half-days — supposedly it gave teachers time to plan — the drawbacks had long since come to dominate. Fairfax had one of the shortest elementary school weeks in the Washington area and, as was underscored by the extension of the just-concluded school year to make up for snow days, there was no give in the schedule.

“It needs to happen. It’s quite obvious, actually,” was the understatement from Schools Superintendent Karen Garza. She told us that, as a former elementary school principal, she knows the demands and expectations placed on them. “How in the world do you cover it all” is the question she remembers posing to principals about the abridged instruction. The answers she got made half-day Monday a priority to be examined.

Details of the added instruction, estimated to cost $7 million, are still being worked out, but officials are right to be aggressive in bringing about a change. As Ms. Garza said, “It’s good for children, so it’s the right thing to do.”

Chantilly High School tennis coach Karen Kegerreis peeks into a school bus in Fairfax County. (Toni L. Sandys/THE WASHINGTON POST)