Many high‑school students find it hard to fall asleep early. Their bodies naturally want to stay up later. Because of this, waking up for early classes becomes a big problem.
During a school week the trouble gets worse. Teens start the week already short on sleep, and the early start time adds more sleep loss each day.
Dr. Oskar Jenni from the University of Zurich says that not getting enough sleep hurts mental health, physical growth, and learning. He points out that teenagers’ natural sleep patterns keep them from going to bed early enough.
Testing a Flexible Schedule
Researchers Joëlle Albrecht, Reto Huber and Oskar Jenni studied a school in Gossau, Switzerland. Three years ago the school allowed students to choose when to start their day.
Students could take optional lessons before the regular classes begin, during lunch, or in the afternoon. They could arrive as early as 7:30 a.m. or wait until the regular start at 8:30 a.m.
The team surveyed the pupils twice. The first survey was taken when school started at 7:20 a.m. The second survey happened a year after the flexible system began. In total, 754 students, about 14 years old on average, answered the questionnaires.
More Sleep When Start Times Are Later
Almost all students (95 %) chose the later option. On average they began school 38 minutes later than before.
Because bedtime stayed about the same, waking up 40 minutes later gave them extra sleep. On school days they slept roughly 45 minutes longer.
Better Sleep Improves Health and Learning
The study, published in the Journal of Adolescent Health, suggests that flexible start times can cut chronic sleep loss. More sleep was linked to better mood, lower stress, and higher grades.
A 2022 Swiss health report found that nearly half of children aged 11‑15 often feel sad, anxious, or tired. Giving teens the chance to start school later could help reduce these problems.