Do Schools Begin Too Early? The effect of start times on student achievement

What time should the school day begin? School start times vary considerably, both across the nation and within individual communities, with some schools beginning earlier than 7:30 a.m. and others after 9:00 a.m. Districts often stagger the start times of different schools in order to reduce transportation costs by using fewer buses. But if beginning the school day early in the morning has a negative impact on academic performance, staggering start times may not be worth the cost savings.