The Impact of Homogeneous Grouping on Achievement and Equity

          In this Review of Educational Research article, Eder Terrin and Moris Triventi (University of Toronto) say that almost all students in industrialized nations start school in heterogenous groups and are taught the same curriculum. But at some point, many students are sorted into different groups based on achievement, interests, and attitudes. This has a significant impact on students’ school performance, educational pathways, access to higher education, and the kinds of work they do after school. 

          Terrin and Triventi did a meta-analysis of research on this sorting process (a.k.a. streaming, tracking, ability grouping) in secondary schools to see what studies have found about its effectiveness – does it produce better overall student achievement? – and its impact on equity – does it change the relationship between family background and students’ school and life trajectories? 

          A number of arguments have been made for homogeneous grouping of students, including:

• Teachers can tailor their instructional strategies to students’ abilities and interests. 
• This specialization allows teachers to work more efficiently and effectively. 
• All students can maximize their potential and learn more. 
• The learning process is more effective, producing higher overall levels of student achievement. 
• If the achievement of lower-group students increases more than that of their higher-group peers, inequality will decrease. 
• Grouping students by their achievement, attitudes, and interests encourages students to take an educational and career pathway that suits them best – academic or vocational. 
• This can lead to greater student and adult satisfaction and lower dropout rates.

 Conversely, arguments have been made for heterogeneous grouping of students: 

• Students tend to be sorted according to family background, with more-advantaged children in the higher-achieving groups and less-advantaged children in lower groups. 
• Groups with higher-achieving students have more-rigorous instruction and curriculum than the lower groups. 
• There’s a peer-group effect; learning with higher-achieving students provides mutual advantages – and the opposite is true in lower-achieving groups, where lower self-esteem and negative attitudes toward schooling can create a less-favorable climate for teaching and learning. 
• There’s also teacher sorting, with more-experienced teachers opting to teach the higher-achieving groups and novice teachers working with the lower groups. 
• There’s evidence that per-pupil expenditures, the demands of the curriculum on students, and teachers’ expectations differ by curriculum level, within and between schools. 
• The earlier student sorting occurs, the more likely it is that decisions are influenced by cultural and other biases, consigning some students to less demanding instruction. 
• Homogeneous grouping therefore intensifies the inequalities with which students enter school and unfairly skews educational and life outcomes along social-class lines. 

          In their meta-analysis, Terrin and Triventi examined the trade-offs between efficiency and equity – between the purported benefits of homogeneous grouping on overall student achievement and the possible negative impact on how achievement is distributed. What did this analysis reveal? 

          First, the impact of homogeneous grouping on student achievement “is nul” – in other words, the supposed efficiency of grouping secondary students by achievement, attitudes, and interests does not produce a higher overall level of student achievement, nor does it result in lower overall achievement. There’s no measurable difference. 

          Second, the meta-analysis found that homogeneous grouping has a negative impact on equity. The research evidence, say Terrin and Triventi, “provides no support for the existence of an ‘equality-efficiency trade-off’ – that is, the need to sacrifice equality to improve the overall performance of the educational system. Instead, this finding suggests that the stream of literature that emphasizes the role of tracking in enhancing both student achievement dispersion and inequality of opportunity relies on more solid empirical evidence than the theoretical arguments suggesting that tracking increases efficiency.” 

          The authors acknowledge that teaching students in heterogeneous groups at the secondary level is pedagogically challenging and educators need to be nimble and innovative to help all students learn at high levels. [See Memo 924 for an article addressing this issue.]

“The Effect of School Tracking on Student Achievement and Inequality: A Meta-Analysis” by Eder Terrin and Moris Triventi in Review of Educational Research, April 2023 (Vol. 93, #2, pp. 236-274); the authors can be reached at eder.terrin@unitn.it and moris.triventi@unitn.it.

Please Note: This summary is reprinted with permission from issue #979 of The Marshall Memo, an excellent resource for educators.