U.S. TIMSS Achievement Gaps 2023: Math, Science and Gender
TIMSS 2023 measured U.S. mathematics and science achievement in grades 4 and 8. The U.S. average exceeded the TIMSS international average in all four grade-subject combinations, while male students scored higher than female students in each U.S. comparison.
Achievement gaps are reported in two distinct ways: the difference between male and female average scores and the much wider spread between students at the 90th and 10th percentiles.
2023 U.S. Achievement Gap Statistics
The gender comparison and percentile spread measure different parts of the achievement distribution and should be interpreted separately.
Male and Female TIMSS Scores
Average U.S. scores for mathematics and science at grades 4 and 8.
2023 Scores by Grade, Subject and Gender
Male students had higher average scores in each of the four U.S. comparisons.
NCES marks each 2023 male-female difference shown here as statistically different at p < .05. Reported scores are rounded; official comparisons use unrounded estimates.
U.S. TIMSS 2023 Score and Gap Matrix
Overall achievement, international comparison, male and female scores, and the 90th–10th percentile spread are shown on the same TIMSS scale.
| Grade | Subject | U.S. Avg. | Intl. Avg. | U.S. Margin | Male | Female | M–F Gap | 10th Pctl. | 90th Pctl. | 90–10 Gap |
|---|---|---|---|---|---|---|---|---|---|---|
| Grade 4 | Mathematics | 517 | 503 | +14 | 526 | 508 | 18 | 384 | 637 | 254 |
| Grade 8 | Mathematics | 488 | 478 | +10 | 495 | 481 | 14 | 366 | 612 | 246 |
| Grade 4 | Science | 532 | 494 | +38 | 536 | 529 | 7 | 404 | 645 | 241 |
| Grade 8 | Science | 513 | 478 | +35 | 519 | 508 | 11 | 385 | 634 | 249 |
The official grade 4 mathematics percentile gap is 254 points even though the displayed rounded percentile scores, 637 and 384, differ by 253. TIMSS calculates reported differences from unrounded estimates.
Achievement Spread and International Position
Two supporting views separate within-U.S. score dispersion from the U.S. position relative to the TIMSS international average.
90th–10th Percentile Score Spread
The spread spans more than 240 scale points in every grade-subject combination.
Percentile gaps compare positions within the full U.S. achievement distribution. They are not gender gaps.
U.S. and TIMSS International Average Scores
The U.S. average was above the corresponding international average in all four comparisons.
The international average gives each included non-benchmarking education system equal weight; it is not a student-weighted global average.
Changes Since TIMSS 2019
Mathematics scores fell between 2019 and 2023. Science averages were numerically lower, but NCES did not identify those science changes as measurable differences.
| Grade | Subject | 2019 Avg. | 2023 Avg. | Change | 2019 Gender Result | 2023 Gender Result |
|---|---|---|---|---|---|---|
| Grade 4 | Mathematics | 535 | 517 | −18 | Male +11 | Male +18 |
| Grade 8 | Mathematics | 515 | 488 | −27 | No measurable difference | Male +14 |
| Grade 4 | Science | 539 | 532 | −7, not measurably different | Male +5, caution | Male +7, caution |
| Grade 8 | Science | 522 | 513 | −9, not measurably different | No measurable difference | Male +11 |
What the 2023 Gap Measures Show
Gender differences, percentile spreads and international-average differences answer separate questions about U.S. TIMSS performance.
Gender Gaps Are Smaller Than Achievement Spreads
Male-female gaps range from 7 to 18 points, while 90th–10th percentile spreads range from 241 to 254 points. The percentile measure captures variation across the broader U.S. score distribution rather than a difference between two reported gender groups.
Mathematics Shows the Larger Gender Differences
The male-female gap is 18 points in grade 4 mathematics and 14 points in grade 8 mathematics, compared with 7 and 11 points in science. Gap size alone does not indicate the overall achievement level of either subject.
Grade 8 Gaps Returned in 2023
Grade 8 mathematics had no measurable male-female difference in 2019; the 14-point 2023 difference was the first measured U.S. grade 8 mathematics gender gap since 2003. Grade 8 science also returned to a male advantage after no measurable difference in 2019.
Data Sources, Scale and Measurement
International Association for the Evaluation of Educational Achievement (IEA), Trends in International Mathematics and Science Study (TIMSS), 2023; U.S. results reported by the National Center for Education Statistics.
U.S. students in grades 4 and 8 were assessed in mathematics and science. TIMSS is administered every four years.
Scores use a 0–1,000 scale with a TIMSS centerpoint of 500 and a standard deviation of 100.
The NCES result tables report average scores for male and female students. The gender gap shown here is the reported male score minus the reported female score.
The achievement spread is the official difference between the 90th- and 10th-percentile scores within the U.S. distribution.
The TIMSS international average is calculated across included non-benchmarking education systems with each education system weighted equally.
Displayed scores are rounded to whole points. Official differences are calculated from unrounded estimates, so subtraction of displayed values can occasionally differ by one point from the published gap.
TIMSS results are descriptive estimates from sampled students and schools. Score differences do not identify causes of achievement differences, and gender gaps should not be interpreted as explanations for the broader 90th–10th percentile score spread.
For grade 4, the U.S. weighted school participation rate was 63 percent before replacement schools and 82 percent after replacements; the combined school, classroom and student participation rate with replacements was 76 percent, meeting the TIMSS Category 2 requirement. For grade 8, the corresponding school rates were 55 percent and 72 percent and the combined rate was 63 percent. Grade 8 met Category 3 criteria but did not meet the overall international participation-rate guidelines. U.S. grade 8 results remain included in the TIMSS international tables and international average with the applicable annotation.