Does early start time of classes affect the grades of high school students

Studies have demonstrated that unique sleep issues affect adolescents. Reports show that adolescents suffer from sleep deprivation that contributes to sleepiness, irritability, poor behavior, school tardiness and absence, vulnerability to accidents, increased use of alcohol and drugs, and difficulty performing cognitive tasks. Early start times in high schools have been implicated in adolescent sleep insufficiency. The research on the impact of sleep in the lives of adolescents has been looked at from many perspectives, but the effect of sleep deprivation on school grades has not been investigated, except by student self-report. Since research demonstrates that sleep deprivation affects adolescents most in the morning hours, the purpose of this study was to compare the grades of high school students in academic classes that started and ended before 9:30 am to the grades of students taking the same course taught by the same teacher later in the day. The grade averages from 1218 paired classes were evaluated for difference.;Statistical analysis of the data revealed strong evidence that grades from early morning classes are lower than grades from the same class later in the day. Grades for science and language classes showed statistically significant differences between the lower morning grades and those later in the day. Early high school class time seems to adversely affect the grades of students in those classes.