Many U.S. high schools start classes before 8:00 A.M., yet research on circadian rhythms suggests that students' biological clocks shift to later in the day as they enter adolescence. Some school districts have moved to later start times for high schools based on the prospect that this would...

Although previous research has shown that homework improves students' academic achievement, the majority of these studies use data on students' homework time from retrospective questionnaires, which are less accurate than time-diary data. However, most time-diary data sets do not contain outcome...