As part of the larger ExpandED Schools initiative, three Baltimore elementary schools (Hilton, George Washington, and Harlem Park) have added three hours to their school day. The three-year program promises schools thirty-five percent more instructional time at only ten percent greater cost.

The hope, of course, is that a dramatic extension of the school day will translate into better test scores and more well-rounded students. And there’s reason to be optimistic. Several New York City schools piloted the program in 2008, and in 2011 the students who participated showed significant test score gains against the rest of the city’s students. The New York ExpandED schools also saw greater attendance, in itself equal to seven additional school days.