As long as school has existed, students have wanted to spend less time there. But for the first time, a study in the US has shown that giving primary school kids a three-day weekend doesn't appear to have a negative impact on academic performance - in fact, the results suggest it can even boost some test scores.

The study looked at the effect of the four-day school week on the reading and maths scores of children in years 4 and 5 in Colorado. While the shortened week wasn't associated with a change in reading ability, maths test scores were significantly higher among children who went to school one day less a week.

The research comes at a time when a large number of schools in Colorado, New Mexico, and Wyoming have already cut back their weeks to four long days, and other states are considering following their lead to reduce costs. To be clear, the four-day school week contains the same amount of hours as a traditional school week, but they're just condensed into four days rather than five.

"What interested me about our results is they were completely opposite to what we anticipated," Mary Beth Walker, one of the researchers from Georgia State University, said in a press release. "We thought that especially for the younger, elementary school kids, longer days on a shorter school week would hurt their academic performance because their attention spans are shorter. Also, a longer weekend would give them more opportunity to forget what they had learned."

But the results showed the opposite. The study looked at the number of students in each school that scored "proficient or advanced" on state-wide maths and reading tests, both before and after the school changed to a four-day week.

On average 55.5 percent of a school's students were achieving these top scores in their maths tests the year before they switched to a four-day week, but after changing, 63.1 percent were getting those results.

This improvement increased over time, with an average of 72 percent of students scoring "proficient or advanced" on their maths tests two years after they’d switched to a four-day school week.

Obviously the study only shows a correlation between the four-day school week and better academic performance, and doesn't prove that the reduced days in class directly impacted test scores. The researchers also admit that they can't yet explain exactly how having a three-day weekend would benefit the kids' scores. But they do have some suspicions.

"My own personal hypothesis is teachers liked it so much - they were so enthusiastic about the four-day week - they did a better job," said Walker. "There’s some evidence in other labour studies that four-day work weeks enhance productivity."

This initial study was only conducted in rural school districts, and further research is needed to show whether the four-day school week can also benefit those living in big cities, as well as to provide some insight into exactly why they work.

But for now the early evidence would suggest that cutting a day off the school week doesn't negatively impact academic performance. And if it helps schools save money, and potentially also helps students and teachers get more engaged in education, then it could be a very good thing.

We just hope that once schools begin to catch on to the benefits of the three-day weekend, workplaces might begin to do the same. Because honestly, who couldn't handle working a few longer hours Monday to Thursday to get Fridays off?

The research has been published in the journal Education, Finance and Policy.

Update 31 August 2015: We had previously listed the improvement in reading test scores, but as the change wasn't stastically significant we've removed this from the article.