Education does increase IQ. The strongest evidence, a meta-analysis by Stuart Ritchie and Elliot Tucker-Drob (2018), found that each extra year of schooling raises IQ scores by roughly 1 to 5 points, and the gains appear to last into adulthood. The relationship runs both ways: children with higher IQ scores also tend to get better grades and stay in school longer.
Untangling those two directions is the hard part. This page covers how researchers did it, how strongly IQ predicts school results, where effort and personality come in, and what this means for gifted screening.
Does education increase IQ?
The obvious data cannot answer the question. People with more education score higher on IQ tests, but people who score higher are also more likely to stay in school. A simple correlation mixes both effects.
Ritchie and Tucker-Drob gathered studies that used designs able to separate them, pooling data from more than 600,000 people. Three kinds of design stood out:
| Design | How it works | Estimated gain per extra year of school |
|---|---|---|
| Controlling for earlier IQ | Compares people who had the same IQ in childhood but later got different amounts of education | About 1 point |
| Policy changes | Uses reforms that raised the compulsory school-leaving age for some birth cohorts but not others | About 2 points |
| School-entry cutoffs | Compares children of nearly the same age who, because of a birthday cutoff, have had a year more or less of school | About 5 points |
Each design has weaknesses, but they point the same way, which is why the result is taken seriously. The school-age cutoff design gives the biggest estimate, probably because it measures young children close to the schooling itself. The policy-change studies matter most for the long run, since they track people who were tested years or decades later, and they show the effect does not simply fade.
A gain of a few points per year sounds small, but it accumulates. It is probably one of the reasons scores rose across the twentieth century as schooling expanded, the pattern known as the Flynn effect, and a likely contributor to differences in average scores between countries with very different school systems.
What exactly improves
The open question is whether schooling raises general ability itself or the specific skills that IQ tests sample, such as vocabulary, arithmetic and familiarity with abstract problems. Ritchie and Tucker-Drob could not settle this with the data available. A study of older Scottish adults by Ritchie, Bates and Deary (2015) found that the association between education and later test scores ran mainly through specific skills rather than the general factor. That still matters: those skills are useful, and they are part of what IQ scores reflect. For more on what can and cannot shift scores, see whether IQ can change over time.
How well does IQ predict school performance?
Very well, by the standards of psychology. The best-known evidence is a study by Ian Deary and colleagues (2007) of more than 70,000 English children. They took the Cognitive Abilities Test at age 11 and their national GCSE exams at about 16.
The correlation between a general intelligence factor at 11 and overall exam performance five years later was about 0.81, measured as a latent correlation that removes some measurement error. The strength varied by subject. It was highest for mathematics and lower for practical and creative subjects such as art and design.
A correlation of 0.81 is high, and yet it leaves room for the many students who did better or worse than their age-11 scores predicted. Meta-analyses of the more ordinary relationship between IQ and school grades find correlations around 0.5, strong but well short of destiny.
IQ, grades and achievement tests are not the same thing
It helps to separate three measures that people often blur:
- IQ tests aim to measure reasoning and problem-solving with content most people have been exposed to.
- Achievement tests, such as state assessments, the SAT, ACT or GCSE exams, measure what students have learned in specific subjects. They correlate strongly with IQ but also reward instruction and practice.
- Grades reflect learning plus effort, homework, attendance, classroom behavior and a teacher's judgment. They are the measure least tied to IQ and most tied to habits.
IQ vs. conscientiousness: what matters more for grades
Personality, especially conscientiousness, predicts school performance largely independently of intelligence. A meta-analysis by Arthur Poropat (2009), covering about 70,000 students, found that conscientiousness predicted academic performance about as strongly as intelligence did. The link between intelligence and grades weakened at higher levels of education, while the link with conscientiousness held steady.
Part of the reason is restriction of range. By college, students have been filtered on ability, so differences in IQ among them are smaller, and effort and organization account for more of the remaining differences. In a well-known study of eighth graders, Angela Duckworth and Martin Seligman (2005) found that a composite measure of self-discipline predicted final grades better than IQ did.
The useful conclusion is not that one trait wins. They add together. A student with strong reasoning and steady work habits has a large advantage; a student with one but not the other can often close much of the gap through the other.
Gifted programs and screening in the US
In the United States, decisions about gifted and talented programs are made by states and school districts, not the federal government, so the rules vary widely. Many districts use a group-administered ability test, sometimes alongside achievement scores, teacher ratings and portfolios. Cutoffs differ: some use national percentiles, some use local norms within the district or school, and the required percentile ranges from the top few percent to a broader band.
How children enter screening matters as much as the test. When identification depends on referral by a parent or teacher, children from low-income families and from groups underrepresented in gifted programs are referred less often. David Card and Laura Giuliano (2016) studied a large Florida district that for several years screened every second grader. The share of low-income and Black and Hispanic students identified as gifted rose substantially, showing that many qualifying children had simply never been tested.
If you are a parent weighing a gifted evaluation:
- Ask your district what tests it uses, at what grade, and what score or combination of measures qualifies.
- Remember that a single group test given on one morning has measurement error. A child just below a cutoff is not meaningfully different from one just above it.
- For questions about giftedness alongside learning or attention difficulties, an individual assessment by a licensed psychologist using tests such as the WISC-V is the right route. This page is general information, not educational or medical advice.
Online tests, including ours, are not designed for school placement. Ours compares you with the people who have taken it and is not a substitute for a district screening or a clinical evaluation. You can read what "gifted" and "genius" scores mean for context on score levels.
Does higher IQ lead to more years of education?
Yes, on average. Tarmo Strenze's (2007) meta-analysis of longitudinal studies found that intelligence measured in youth correlates about 0.56 with the amount of education people eventually complete, a stronger link than with either occupation or income.
Education then feeds back into scores, which helps explain why the correlation between IQ and attainment is so persistent. A student who scores well early is more likely to stay in school, and staying in school raises later scores. Both effects run alongside family resources, which shape access to schooling and the test scores children bring to it. For what this means later in life, see how IQ relates to income and success.
What this means for you
If you are an adult wondering whether more education will make you smarter, the evidence says learning keeps doing measurable good, and the gains from schooling seem to persist. The effect per year is modest, and most of it shows up in knowledge and skills rather than a dramatic shift in raw reasoning. A free online test is not a good way to measure that change: a repeat sitting is inflated by practice effects, and small differences fall within the range of error.