New randomised controlled trials investigating best practice in grouping students published today

News Release

Friday 7 September 2018

A new Education Endowment Foundation (EEF) study to find out how schools can group pupils in ways that benefit all pupils has been published today.

The EEF commissioned UCL Institute of Education to investigate best practice in grouping students by attainment. The study, which consisted of two randomised controlled trials (RCTs), was independently evaluated by a team from the National Foundation for Educational Research (NFER). The principal investigator for this trial was Dr Ben Styles, Head of NFER’s Education Trials Unit and the day-to-day trial manager was Palak Roy, Senior Trials Manager from NFER’s Centre for Statistics.

The two reports, Best Practice in Mixed Attainment Grouping and Best Practice in Setting, address the widespread, yet controversial, practice of grouping students into classes by ability at secondary school in England.

The first, a pilot RCT, explored the possibility of randomising schools to ‘Best Practice in Mixed Attainment’ teaching. It demonstrated that, despite existing evidence that grouping by ability may harm outcomes for disadvantaged pupils; schools are largely reluctant to participate in an evaluation of mixed attainment teaching.

The second study was a large efficacy trial that took a more realistic approach. Instead of asking schools to change their grouping practices in a radical fashion, it attempted to tweak existing practice in ways that might improve learning, particularly for lower attaining pupils. Due to problems with implementation by schools and high attrition rates for follow-up testing, it was difficult to conclude anything certain about the impact of the ‘Best Practice in Setting’ intervention from the results of this trial. There was no evidence that it improves attainment or self-confidence.

Ben Styles, Head of NFER’s Education Trials Unit, said: “It is rare that we get the opportunity to evaluate a practice that is so widespread in English schools so it was disappointing that many felt unable to engage fully with the intervention and outcome testing. Any future research in this area should focus on interventions that have been developed in close collaboration with teachers so we can be more certain they will be embraced to the extent necessary for a large scale randomised controlled trial.”

Findings from both reports are available to view below.


Best Practice in Setting
Best Practice in Mixed Attainment Grouping