Sleepy Kids Learn Less
I’ve posted before that ever though most homework doesn’t seem to help learning, I predict we’ll keep assigning it, “to get kids used to doing a lot of work, in preparation for their future industry era jobs.” Similarly, I predict we’ll keep making kids start school early, even though that hurts learning:
This study identifies the causal effect of school start time on academic achievement by using two policy changes in the daily schedule at the US Air Force Academy along with the randomized placement of freshman students to courses and instructors. Results show that starting the school day 50 minutes later has a significant positive effect on student achievement, which is roughly equivalent to raising teacher quality by one standard deviation. (more)
Purely anecdotal, but I lived through this change (USAFA '09). Holy cow, did it make a difference. Walking to breakfast in the dark was horribly depressing, and shifting everything later increased productivity and participation in extracurricular activities.
With small kids and no stay at home parent, "wrap-around" care is required. With parents who need to go to work early, the wrap-around would include more at the early end and less after school.