ABILITY GROUPING? DOES IT MATTER?
Grouping students by ability is often suggested as a way for teachers to provide greater diversified instruction to students, and to better teach to the individual abilities within a class. After all, as teachers, we often have students with abilities that differ by multiple grade levels. That all being said, grouping student’s by their ability does present some possible risks, especially for students in the lowest-performing groups. Research into labeling theory and the impact of expectations has shown that students who perceive themselves to be labeled as less intelligent are likely to create a self-fulfilling prophecy. “Labelled students” often try less hard and expect less of themselves. Moreover, research has shown that teachers can lower their expectations for “labeled students” spend less time helping “labeled students” and also generally contribute to a negative self-fulfilling prophecy for students identified as being less intelligent. Advocates against ability grouping, also often argue that having gifted students work with struggling students benefits the struggling students, both by increasing the expectations of the struggling students and by inadvertently providing some peer tutoring.
On the other hand, it could be argued that having gifted students work with struggling peers, for the sake of their struggling peers, could be unfair to the gifted student. After all, what is best for the class as a whole, might not be the best for the gifted student. Ultimately, this might be not a question of scientific efficacy, but of philosophical value. Do we take the utilitarian perspective and do what’s best for the group? Or do we place the needs of the individual on a higher pedestal?
This debate is not a modern one, but rather one that has been ongoing for the past 100 years. Indeed there have been at least 11 meta-analyses of the topic over the past 30 years and more than 280 individual quantitative studies of the subject.
Kulik and Kulik did a meta-analysis of the topic in 1987, and 1992. Their studies found Hedges g effect sizes of .22 and .29. Robert Slavin conducted a meta-study in 1987 and found a Hedges g effect size of .39. Monstellar and et al did a meta-study in 1996 and found a Hedges g effect size of .19. On average these studies found an average effect size of .27. This is a statistically significant effect size; however, it is still a low one. Examining this data would suggest that grouping students by ability might provide an overall benefit. However, I would argue that this benefit is too small to be worth the opportunity cost for teachers’ time. Moreover, I would personally recommend a more fluid approach based on learning goals for grouping, not a fixed approach based on ability. For more information on this idea, please read our article on Podding. Or listen to our podcast episode on Podding: https://podcasts.apple.com/ca/podcast/podding-episode-14/id1440404959?i=1000434292106 To contextualize these ability grouping effect sizes, I have graphed these effect sizes below, but also included some high yield strategies, to provide a comparison.
While the overall effect size of ability grouping suggests a minor benefit. We cannot just consider how ability grouping affects the whole class, but rather we need to consider the impact of ability group on each ability level. Kulik and Kulik’s 1987 study looked at precisely this. Their study found a .33 effect size for the high group, a .34 effect size for the medium group, and a .23 effect size for the low group. As I alluded to at the beginning of this article, I found the idea of grouping students, concerning, as I could see some potential detriments for the lowest-performing students. However, upon looking at this specific data, it does not appear that those concerns are reflected within the data. That being said, just because the students did not show negative results within the context of these studies, does not mean that placement in the lower levels of groups did not negatively impact student self-esteem.
