Scientists Find Surprisingly Simple Way To Improve People's Grades. All It Costs Is $52 A Semester

"Findings showed that greater early-term total nightly sleep duration predicted higher end-of-term GPA, an effect that persisted even after controlling for previous-term GPA and daytime sleep," one study explains.

"Specifically, every additional hour of average nightly sleep duration early in the semester was associated with an 0.07 increase in end-of-term GPA."

Unreliable narrators

So if we just nagged more, and students promised to get some more sleep, everyone will begin to get better grades, right? 

One of the problems is that students don't appear to be aware of how little sleep they are actually getting. In the study, the average student slept 6.6 hours a night, less than the recommended 7 hours or more for adults, with half of students going to bed after 1 am on average, and a quarter staying up until after 2 am.

"Two-thirds told us they usually slept seven hours – the trackers showed only about one-third of students slept that much on even three nights out of five," the researchers write in a piece for The Conversation. "94% said their ideal night of sleep was longer than the one they were getting."

The study was not aimed at finding further evidence that poor sleep is associated with poor grades, but at finding an effective intervention. Nearly all of the 1,100 students studied said that they wanted to get more sleep, and the research was aimed at how this could be achieved effectively.

How to encourage a good night's sleep

The team found that reminders at bedtime, as well as feedback in the morning, had little effect on sleep patterns. So maybe nagging isn't the best option after all. 

However, there was an effective method that improved the sleep of the students studied, with an associated improvement in their grades. 

That method? Paying the students $5 a night to get their full 7 hours in. 

Students who were in the group that was paid to sleep went on to get 19 minutes more sleep per school night on average, with their GPA rising by around 0.08 points in the same semester. Grades remained higher in the semester after that too.

The team found that timing of the intervention and payment mattered, with the more effective payments coming on a daily basis rather than a lump sum at the end. They also found that sleep intervention was more effective in the first semester when sleeping habits had not yet been formed.

All in all, it appeared to be a fairly cost-effective intervention, at an estimated $52 per participant per semester for improvements in the students' grades. 

"Only a handful of interventions surpass ours in terms of impact, but they come with a two to five-fold higher cost per participant," the team writes in their paper. 

"In particular, our intervention compares favorably to achievement incentives that condition rewards on GPA."

Changing routines

Looking at the economic backgrounds of the students, the team found that there was little difference in effect between affluent and disadvantaged students, meaning that it could potentially be used on everybody.

Though they often demonstrate impressive improvements in grades, unfortunately these studies don't often end up being adopted as a policy matter. Don't expect to be paid to sleep anytime soon. 

However, the team believes that some improvements could be made by universities.

"Late evening deadlines to submit assignments and early classes can both make it harder for students to get enough sleep," the team writes in The Conversation. 

"Changing some of these features costs little compared with many academic support programs, and it may be worth testing alongside other interventions aimed directly at students."

"Very few universities or students treat sleep as part of an investment in education, or ask whether the schedules and incentives schools create make adequate sleep harder. Our results suggest they should," they added.

The study is published in the Journal of Political Economy.