As energy costs rise, rural school districts across the country may follow the lead of the 100 or so schools in 16 states that offer classes just four days a week. Cutting out a day of heating, cooling, and transportation fuel — which can be significant in spread-out districts where school buses might travel 100 miles round trip each day — allows schools to put funds toward valuable programs and staff. Advocates say four-day weeks can also improve student attendance and performance (though at least one district switched back to a five-day week after concluding that effective teaching and learning dropped off at the end of an extended day). Kentucky’s Webster County School District switched to a four-day week in 2004, and has cut total costs by 3.5 to 4 percent. “If we were to go back to a five-day week,” says Superintendent James Kemp, “the school board and I would be run out of town.”