Teaching maths in sets does not negatively impact disadvantaged students or low prior attainers, research has found.

Researchers from UCL Institute for Education, on behalf of the Education Endowment Foundation (EEF), investigated the impact of different grouping practices in maths teaching in the first two years of secondary school.

The study, which took place between 2022 and 2024, also revealed that teaching maths in sets improves progress by up to two months for high-attaining students in Years 7 and 8.

Analysing data from 97 state schools, researchers found that students in schools using mixed-attainment groups made one month’s less progress in maths, on average, compared with students in schools with sets.

The researchers conducted the study by examining schools that were “deliberately made as similar as possible on a broad range of observable characteristics” before comparing outcomes.

Of the 97 schools that participated, 28 taught maths to mixed-attainment groups and 69 used setting by attainment.

Disadvantaged students

Researchers found that students eligible for free school meals (FSM) made similar progress in maths whether they were taught in sets or in classes with students with varied attainment.

The researchers compared standardised test scores in Years 7 and 8 and between the two types of setting.

The report states: “For the sub-group of students in receipt of FSM, there was effectively no difference in attainment, indicating that, contrary to some qualitative evidence, students from disadvantaged backgrounds are not further disadvantaged by the practice of setting.”

While the study indicates no significant changes between the attainment of FSM students in different groupings, the researchers did see differences in confidence levels.

Students eligible for FSM reported slightly lower confidence in their maths ability when they were taught in groups with varied levels of attainment rather than in sets.

Students with low prior attainment

Using key stage 2 (KS2) Sats scores, the researchers grouped students based on their prior attainment, and compared their progress when taught in sets with similar ability and in groups with mixed attainment.

The researchers found that students with low prior attainment in KS2 maths made similar progress in maths, whether they were taught in sets or not.

While the study found no difference in the progress, the researchers indicated there is less “security” in this conclusion, because the cohort of students was smaller.

Students reported lower levels of self-confidence in mixed-attainment groups compared with those in sets overall, but this was most pronounced among low prior attainers.

The report states that the impact on confidence for low prior attainers was “moderate” compared with “small” for FSM students and the cohort overall.

Students with high prior attainment

The researchers found that those most impacted by different groupings were high-attaining students.

According to the report, students with high prior attainment in KS2 maths saw their progress slow by two months when they were taught in schools with mixed groups rather than sets.

Similar to the findings on low attainers, the EEF says these results may have “lower security” than the overall findings because of the smaller number of students.

Overall, the report says that teaching students in groups with mixed attainment did slow progress by up to one month compared with teaching in sets.

Although the researchers said there was “uncertainty around the result” as some students saw progress slow by two months and some did not see any reduction at all.

While most schools teach students in sets based on attainment, critics have said it is “very hard to find evidence to suggest setting and streaming boost attainment” for all pupils.

‘Strongest evidence to date’

Professor Becky Taylor, of the UCL Institute of Education, said the study “provides the strongest evidence to date” on attainment grouping.

Professor Becky Francis CBE, chief executive at the EEF, said the study was an “important step forward” in understanding how students are affected by different methods of grouping.

“While this is something people have passionate views on, there’s so much we don’t know,” she said. “Much of the existing evidence is from other contexts and countries.”

She added: “These results contribute to our understanding of good practice in maths. We hope more research can expand our understanding on this important topic.”

While many schools teach students in sets based on attainment, critics have said it is ”very hard to find evidence to suggest setting and streaming boost attainment” for all pupils.

Arranging classes in sets is a contentious issue. Previous EEF research found that setting had, on average, no discernible impact on student progress in schools.

David Hatchett, CEO at Anthem Schools Trust, which runs 11 primary schools and four secondaries, has argued for setting to be banned to help stop “capping the potential” of young people.

In March he wrote that setting “only really benefits the teacher” and that the philosophy behind it “is shaped by adult convenience rather than children’s learning”.