U.S. TIMSS Results Over Time: 1995–2023
U.S. Trends in International Mathematics and Science Study results provide a comparable series of average mathematics and science scores for fourth- and eighth-graders from 1995 through 2023.
Mathematics scores fell from 2019 to 2023 at both grades. Science scores did not measurably differ from 2019 at either grade. Across the longer period, the 2023 mathematics averages were not measurably different from 1995, while fourth-grade science was lower than in 1995.
2023 U.S. TIMSS Scores
Average scores are reported on the TIMSS 0–1,000 scale. The fixed scale centerpoint is 500.
U.S. Mathematics and Science Scores Across TIMSS Cycles
Average scores for grades 4 and 8, 1995–2023
Grade 4 has no 1999 observation because TIMSS was not administered at the fourth grade that year. The chart uses a narrowed vertical range to make score movement visible; official TIMSS scale scores run from 0 to 1,000.
U.S. TIMSS Average Scores by Assessment Year
The table combines the official U.S. trend series for mathematics and science. Values are rounded average scale scores.
| Year | Grade 4 Math | Grade 8 Math | Grade 4 Science | Grade 8 Science |
|---|---|---|---|---|
| 1995 | 518 | 492 | 542 | 513 |
| 1999 | Not administered | 502 | Not administered | 515 |
| 2003 | 518 | 504 | 536 | 527 |
| 2007 | 529 | 508 | 539 | 520 |
| 2011 | 541 | 509 | 544 | 525 |
| 2015 | 539 | 518 | 546 | 530 |
| 2019 | 535 | 515 | 539 | 522 |
| 2023 | 517 | 488 | 532 | 513 |
Recent and Long-Term Score Comparisons
A change in rounded scores is not automatically a measurable change. NCES comparisons use unrounded estimates and their sampling uncertainty.
| Series | 1995 | 2019 | 2023 | 2019–23 | 2019 vs. 2023 | 1995 vs. 2023 |
|---|---|---|---|---|---|---|
| Grade 4 Mathematics | 518 | 535 | 517 | −18 | Lower in 2023 | No measurable difference |
| Grade 8 Mathematics | 492 | 515 | 488 | −27 | Lower in 2023 | No measurable difference |
| Grade 4 Science | 542 | 539 | 532 | −7 | No measurable difference | Lower in 2023 |
| Grade 8 Science | 513 | 522 | 513 | −9 | No measurable difference | No measurable difference |
For fourth-grade science, the displayed rounded averages are 542 in 1995 and 532 in 2023. NCES reports the 2023 average as 9 points lower than 1995 because formal score differences are calculated from unrounded estimates.
What the U.S. Trend Series Shows
Recent movement and the nearly three-decade comparison do not produce the same pattern across every grade and subject.
Mathematics: 2019 and 2023
Average mathematics scores fell from 2019 to 2023 by 18 points in grade 4 and 27 points in grade 8. Both changes were measurable in the NCES trend comparisons.
Mathematics: 1995 and 2023
The 2023 mathematics averages were not measurably different from the corresponding 1995 averages at either grade, despite the declines from the higher 2019 levels.
Science Followed a Different Pattern
Science averages in 2023 were not measurably different from 2019 at either grade. Fourth-grade science was lower than its 1995 level, while eighth-grade science was not measurably different from 1995.
The 500 Centerpoint Is Not a Current Average
TIMSS maintains a fixed scale centerpoint of 500 to support trend comparisons. It should not be interpreted as the international average for every assessment year; the 2023 international averages vary by grade and subject.
Data Sources and Measurement
International Association for the Evaluation of Educational Achievement (IEA), Trends in International Mathematics and Science Study, as reported by the National Center for Education Statistics.
NCES figures M5a, M5b, S5a, and S5b provide the U.S. average-score series used in the tables and chart.
TIMSS measures mathematics and science achievement at grades 4 and 8 on a four-year cycle. The United States has participated since the first administration in 1995.
Scores use a 0–1,000 scale with a fixed centerpoint of 500 and a standard deviation of 100. The scale is maintained across assessment cycles for trend comparisons.
TIMSS was not administered at grade 4 in 1999, so the fourth-grade mathematics and science trend series contain seven assessment years rather than eight.
NCES trend figure notes state that the United States did not satisfy TIMSS sample participation guidelines for grade 8 in 2023. Earlier U.S. cycles also include specific participation and population-coverage annotations.
Displayed scores are rounded. NCES tests changes using unrounded estimates and sampling errors, so arithmetic differences between displayed values should not be used alone to determine whether two results differ measurably.
The table reports national U.S. average achievement scores, not state-level results or percentages of students reaching TIMSS international benchmarks. Comparisons describe score patterns and do not establish causes for changes between assessment cycles.