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Facts and Fiction About the So-Called “Summer Slide”

Do children really learn less during summer vacation? Less of what?

Luke Porter, on Unsplash
Source: Luke Porter, on Unsplash

Every summer we hear from educators about the “summer slide” in academic learning (e.g. here and here). The claim is that children lose much of what they gained from school during the summer break, so time is lost catching up in the fall. Some even argue that school should continue through the summer, so as to prevent that loss! Here are a few questions and thoughts that come to my mind whenever I hear about the summer slide:

If children lose academic skills over the few weeks of summer, then did they really ever learn those skills? It must have been pretty shallow learning. (For more on this point, see this essay, by Kerry McDonald.)

If the skills taught in school are lost so easily, then what happens when people finally finish school and go on to life outside of it? Won’t the skills be lost then? If we’re going to force children to stay in school all summer so they don’t lose skills, then maybe we should force all of us to stay in school our whole lives, so we don’t lose skills!

Very often people writing about the summer slide seem to assume that the only learning that is important is learning that occurs in school and is measured on school tests. It’s amazing to me how often this assumption goes unchallenged. As I’ve argued in my book and in many essays in this series, the most important lessons of life cannot be taught and can only be learned in real life. In real life we learn how to make our own decisions, how to create our own activities, how to actually DO things as opposed to memorize things. For schoolchildren, summer is a time for immersion in real life. School, at best, prepares children for more school. Real life prepares children for real life.

The claims about the summer slide led me to be curious about the data. What does the research actually reveal concerning a loss of school learning over the summer? I spent a couple days digging into the research literature, and what I found suggests that much of what we hear about the summer slide is myth.

Research relevant to the summer slide has been going on for about 100 years. Most of the studies referred to by advocates of school through the summer were conducted decades ago (for a review, see Cooper et al., 1996); so I went back and looked at those studies. All in all, the research indicates that, as measured by standard academic achievement tests, there is at least as much academic gain during the summer vacation as there is loss. . Most of the studies have focused on reading and mathematics abilities. Although the results are somewhat inconsistent from study to study, most studies show either no significant change or an increase in reading ability over the summer. The concern seems to be with mathematics, where quite a few studies show a significant decline. That got me curious. Are all kinds of math abilities lost or only some?

Math calculation declines but math reasoning increases over the summer.

I found three research studies in which students were tested just before and just after summer vacation with math achievement tests that separated calculation ability from math reasoning ability, and they all showed that calculation ability declined a bit over the summer but math reasoning increased quite substantially! To me, this is no surprise.

Calculation tests assess the ability to add, subtract, multiply, and divide without error (without a calculator). A typical easy question might be, What is 58 plus 44? A harder question might be, What is 5.291 times 8.3? Students in school generally learn the procedures for doing such calculations by rote, without necessarily understanding why you do it that way. Material learned by rote is pretty easily lost when it isn’t rehearsed. Today, of course, hardly anyone does such calculations outside of school; we all have calculators or computers.

Math reasoning tests assess students’ understanding of math concepts and their ability to use those concepts to solve problems. This, of course, requires much deeper knowledge than the rote memory needed for calculations. A typical easy question might be, How do you determine the area of a rectangle? Or, a harder question might be, If a gallon of paint covers 200 square feet, how much paint do you need to cover all four walls of a room that is 20 ft long, 15 ft wide, and 9 ft high? This question does require some calculation, but first you have to figure out what it is you need to calculate.

Here are the findings of the three studies that separated calculation and reasoning.

Parsely & Powell (1962) tested students, in grades 1-6 at Willoughby-Eastlake public schools in Ohio at the end of the academic year and again at the beginning of the next. For the calculation test (called “fundamentals”) they found a somewhat different pattern of change for each grade level, but, overall, there was no significant gain or loss over the summer. For the reasoning test, most grades showed a significant gain over the summer. When I calculated the average gain in math reasoning, for all grades combined, it amounted to a grade-equivalent of 0.24. Stated differently, they gained as much during summer vacation as they would be expected to gain in a quarter of a year (which is about the length of the summer). The biggest gain—0.55 grade equivalent—was shown by the 6th graders.

Grenier (1973) tested 7th graders in public junior high schools in Griffin, Georgia, at the very end of the academic year, and then re-tested some of them at the very beginning of the next academic year and others two weeks later. Her math test consisted of three components: computation, concepts, and applications. For my purposes, here, I combined the concepts and applications scores, to produce a math reasoning score. Here are Grenier’s results. For computations she found a grade equivalent decline of 0.22 year for those tested immediately at the end of vacation, but a grade equivalent increase of 0.10 year for those tested two weeks later. So, there was a summer slide in computation, but that loss was more than regained within two weeks back at school. For reasoning she found an average grade equivalent increase of 0.48 year. In other words, during the three months of summer vacation they gained nearly half a year in math reasoning ability.

Wintre (1986) tested Toronto elementary school students in grades 1, 3, and 5 at the end of the school year and, again, at the beginning of the next school year. I can't compare her findings directly with those of the other studies, because she reported only the mean raw scores on each test and did not show a conversion to grade equivalency. But the pattern of her results was the same as that for the other two studies. Combining all grades, she found a significant increase (+5.4% in mean score) in math reasoning and a small decrease (-1.7%) in math computation. She also tested word knowledge and reading comprehension and found significant increases in both of those, of +5.2% and +6.2%, respectively.

Which is more important, the ability to perform calculations accurately by hand (which nobody in the real world does any more) or the ability to understand the meanings of mathematical concepts and to apply them to real problems? The former ability increases more rapidly during the school year than during the summer; the latter increases more rapidly during the summer than during the school year.

So, take away summer, and we will produce lots of graduates who know how to do calculations but have no idea why anyone would do them other than to pass a test. But then, of course, they will forget how to do the calculations by a few weeks after graduation, as that is what is lost when not in school.

Maybe instead of expanding the school year to reduce a summer slide in calculation we should expand summer vacation to reduce the school-year-slide in reasoning.

Before closing this essay, however, I must acknowledge that much of the concern about the summer slide has to do with the gap between economically impoverished students and others. It turns out that students from poor families gain less and lose more over the summer, on tests, than do those from families that are more well off. That’s a serious problem, because it is one of the reasons why young people from poor families are derailed from careers that require higher education. I’ll address that problem in my next post. Stay tuned!


Basic Books with permission
Source: Basic Books with permission

And now, what do you think? Are you in favor of expanding or shrinking the academic year? What would be lost if kids lost summer vacation? What would be gained? This blog is, among other things, a forum for discussion, and your views and knowledge are valued and taken seriously by me and other readers. Make your thoughts known in the comments section below. As always, I prefer if you post your comments and questions here rather than send them to me by private email. By putting them here, you share with other readers, not just with me. I read all comments and try to respond to all serious questions if I feel I have something useful to add to what others have said.


Cooper, H., et al. (1996). The effects of summer vacation on achievement test scores: A narrative and meta-analytic review. Review of Educational Research, 66, 227-268.

Grenier, M-A. (1975). An investigation of summer mathematics achievement loss and the related fall recovery time. Doctoral dissertation, University of Georgia, 1975. Available from ProQuest Dissertations and Theses.

Parsley, K. M., & Powell, M. (1962). Achievement gains or losses during the academic year and over the summer vacation period: A study of trends in achievement by sex and grade level among students of average intelligence. Genetic Psychology Monographs, 66, 285-3

Wintre, M. G. (1986). Challenging the assumption of generalized academic losses over summer. Journal of Educational Research, 79, 308-312.

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