In all countries and economies that participated in PISA 2015, socio-economic status has a large influence on students’ performance in science, reading and mathematics. For example, the mean science score among disadvantaged students was 88 points lower than the mean score among advantaged students, on average across OECD countries. This gap is equivalent to about three full years of schooling. However, performance differences between advantaged and disadvantaged students have narrowed over past PISA cycles, on average across OECD countries and in many individual countries and economies. This implies that equity, or the lack of it, is not a fixed feature of education systems. All countries can reduce the impact of socio-economic status on student performance, given the right education policies and practices.

An analysis of data for a single cohort of students who participated in the Trends in International Mathematics and Science Study (TIMSS), PISA and the Survey of Adult Skills (PIAAC) finds that disparities in performance related to socio-economic status develop early – even among pupils as young as 10 – and widen throughout students’ lives. On average across 11 OECD countries with comparable data, about two-thirds of the achievement gap observed at age 15 (PISA) and more than half of the achievement gap observed among 25-29 year-olds (PIAAC) was already seen among 10-year-olds (TIMSS).

Longitudinal data for individual students in five countries show that student performance in PISA is strongly correlated with outcomes in early adulthood. Fifteen-year-old students who scored in the top quarter in reading are between 38 and 53 percentage points more likely to complete university than students who scored in the bottom quarter; and students who scored in the top quarter of reading performance are between 24 and 47 percentage points more likely than students in the bottom quarter of performance to be working in a job that requires tertiary education by the age of 25. Furthermore, differences in 15-year-olds’ reading performance explain between 27% and 43% of the difference in university completion rates between students with and those without tertiary-educated parents. This suggests that reducing the gaps related to socio-economic status in what students learn during compulsory schooling could increase upward educational mobility.

Less household wealth often translates into fewer educational resources, such as books, games and interactive learning materials in the home. In addition, families with limited income may not have access to early education if it is not publicly funded. Many disadvantaged students are concentrated in lower-quality schools. Disadvantaged students attending advantaged schools score 78 points higher than those attending disadvantaged schools, on average across OECD countries; disadvantaged students attending schools with an average socio-economic profile (schools that are neither advantaged nor disadvantaged) score 36 points higher in science than those attending disadvantaged schools.

But the report also finds that, on average across OECD countries, 11% of disadvantaged students across OECD countries score in the top quarter of science performance in their own countries (these students are considered to be “nationally resilient”), 25% score at PISA proficiency Level 3 or above in science, reading and mathematics (“core-skills resilient”), and 26% are satisfied with their life, feel socially integrated at school and do not suffer from test anxiety (“socially and emotionally resilient”). Disadvantaged students who are socially and emotionally resilient also tend to do better academically. This implies that helping disadvantaged students develop positive attitudes towards their education can also benefit these students’ academic development. Academic resilience can also promote social and emotional resilience, creating a cycle of positive reinforcement.

Countries need to consider creating and strengthening policies and programmes that support disadvantaged students. For example, countries can promote greater access to early childhood education and care, particularly among disadvantaged families, as these programmes both provide more equitable learning environments and help children acquire essential social and emotional skills.

Countries can also set ambitious goals for and monitor the progress of disadvantaged students, target additional resources towards disadvantaged students and schools, and reduce the concentration of disadvantaged students in particular schools. They can also develop teachers’ capacity to identify students’ needs and manage diverse classrooms, promote better communication between parents and teachers, and encourage parents to be more involved in their child’s education. Teachers and schools can foster students’ well-being and create a positive learning environment for all students by emphasising the importance of persistence, investing effort and using appropriate learning strategies, and by encouraging students to support each other, such as through peer-mentoring programmes.