What the newest data show

NWEA, which runs the MAP Growth tests many schools use, published its newest estimates in April 2026 from its 2025 national norms (Kuhfeld and Morton):

Summer after Average change in math (RIT points) Average change in reading (RIT points)
Kindergarten −2.0 +0.8
1st grade −5.2 −0.2
2nd grade −6.4 +0.8
3rd grade −5.1 +0.1
4th grade −6.0 +0.1
5th grade −7.3 +0.1
6th grade −4.0 +0.2
7th grade −2.5 +0.6

NWEA says the math drops equal roughly 10 to 30 percent of what students learn in a typical school year, and that reading is essentially flat. The averages hide a wide spread: in most grades, the 10 percent of students with the most summer slide lose more than a year's worth of typical school-year gains in both subjects.

An earlier study of NWEA data from nearly 18 million students found the average student lost 17 to 28 percent of the school year's gains in English and 25 to 34 percent in math over the following summer, depending on grade. Over five summers, 52 percent of students lost ground in English every single summer (AERA, on Atteberry and McEachin's 2021 study).

Why researchers disagree

Estimates of summer loss depend heavily on the test. One comparison found average summer change ranging from a gain of 0.02 SD on one test to a drop of 0.50 SD on another (Kuhfeld and Lewis, 2023). Paul von Hippel, who once wrote about summer loss himself, found that older results don't replicate on modern tests and concluded it "could be serious, or it could be trivial" (Education Next). The one result he found on every test: nearly all children learn much more slowly in summer than during school.

The NWEA researchers say it's less harmful to assume summer losses are real and act on them (Brookings). For a parent, the practical reading is: math slips more than reading, and summer change varies a lot from child to child.

What helps

Approach What the evidence says
Daily reading with books the child chooses Giving children in high-poverty schools 12 self-chosen books to keep each summer, for three summers, raised reading scores (0.14 SD, about the 50th to the 56th percentile) (What Works Clearinghouse)
Summer reading programs Across 41 programs, a modest average effect of 0.10 SD on reading, larger for low-income children; home-based programs built on children reading on their own also helped (Kim and Quinn, 2013)
Summer programs with regular attendance In RAND's study of five-to-six-week programs, children who attended at least 20 days outperformed others, a gain equal to 20–25 percent of a typical year in math and reading; the benefit had faded three years later (RAND, 2020 follow-up)
Enough instruction time Children with about 25 hours of math or 34 hours of reading instruction in a summer did better in that subject the next fall (RAND, 2016)

RAND's findings for high attenders are correlational, not experimental, and it recommends that programs aiming for academic gains run at least five weeks, preferably six, with at least three hours of instruction a day.

A summer plan at home

  • Read every day. Let your child choose the books. For K–2 readers, the phonics at home guide has short routines.
  • Keep math facts and fractions warm. Ten minutes a few times a week matters more in math, where the drops are larger. The math facts guide has a short daily routine, and the fractions guide has practice ideas for grades 3–5.
  • Write something weekly. A letter, a journal entry or a short review of a book or a movie.
  • For a child who is behind, three sessions a week for several summer weeks is closer to what tutoring research supports; one or two a week suits a child who is mostly staying sharp. See how often a child should see a tutor.

Questions parents ask

How much math do kids lose over the summer?

On NWEA's MAP Growth tests, average math scores drop 2 to 7 points over the summer, roughly 10 to 30 percent of a typical school year's learning, with the biggest drops in the elementary grades.

Do kids lose reading skills over the summer?

On average, very little on MAP Growth: reading scores are essentially unchanged from spring to fall. But summer change varies a lot from child to child, and the students with the biggest drops lose more than a year's typical gains.

How much summer reading helps?

In a review of 41 summer reading programs, the average effect on reading was modest, about 0.10 SD, and larger for children from low-income families. Programs that put books in children's hands, such as 12 self-chosen books each summer, have shown gains.

Is summer tutoring worth it?

It depends on the goal. Research on summer programs found benefits mostly for children who attended consistently and got enough instruction, roughly 25 hours of math or 34 hours of reading in one study. For a child who is behind, regular summer sessions can keep skills moving; for a child on track, daily reading may be enough.

Sources