Does size really matter?

Ann-Marie Gibson

During the 12 years I have been teaching in higher education I have taught classes with as few as four postgraduate students and as many as a lecture theatre crammed with 300 first year undergraduate students. Whilst the learning activities and delivery of the material were inevitably different, I’ve always wondered whether being part of a large class is beneficial for student learning?

Previous assumptions in higher education have been ‘less is more’, based on the idea that with smaller class sizes we can build stronger relationships with our students and foster more collaborative learning. On the flip side, larger class sizes allow students to collaborate with a variety of perspectives and more easily regulate their learning without feeling like they’re being monitored. But what does the evidence suggest?

Until recently the evidence consistently found that smaller class sizes correlated with improved academic outcomes, teaching effectiveness, and student evaluations. However, as with any correlation, the relationship between class size and educational outcomes is more complex than this as there are numerous moderating variables than could potentially influence this connection. These include factors related to the students (e.g., student ability, gender, socio-economic status, ethnicity) and those related to the course and teacher (e.g., undergraduate or postgraduate course, discipline, teacher experience).

Another factor to consider at the institutional level is cost. Whilst smaller class sizes may appear to be better for student grades and their evaluations of the teacher, there are financial implications for smaller class sizes in terms of staffing costs, staff availability and space. Spreading students across more classes to reduce class sizes often means employing more teaching staff, and, likely, more first-time teachers. In their study which used a dataset of 25semesters, 276 courses, and 539 teachers, Sapelli and Illanes found that students rated first-time teachers less favourably compared to more experienced teachers. Therefore, higher education institutions face a trade-off between increasing the number of classes yet using first time, inexperienced teachers to deliver these classes if they wish to increase admissions. If institutions do employ more first-time teachers, they need to provide them with better training to help them deliver high quality teaching and learning. At ACU, we are addressing this through our INSPIRE programme which aims to empower teachers to implement the highest-level evidence-based learning and teaching practices, with the best interests of students at heart.

The good news is that the research findings are shifting in terms of our understanding of the impact of class size on educational outcomes, providing evidence that for some scenarios, larger class sizes are not detrimental to educational outcomes for all students.Two recent studies with large sample sizes have explored the complexities of this relationship. Drawing from a robust sample size of 172,516 grades awarded to 32,766 students in 8,049 classes offered across 14 terms, Little and colleagues found that the effect of class size is not uniform and there is a degree of variability when accounting for student ethnicity and gender.For example, in smaller class sizes male students who were African American,Hispanic, and American Indian performed worse relative to their peers, whereasWhite and Asian/Pacific-Islander females had the strongest performance. In contrast, a study in the UK with a sample of 25,000 first year undergraduate students examined the effect of class size on academic performance in STEM and non-STEM subjects. Larger class sizes were associated with significantly lower grades, with a larger effect in STEM subjects yet these effects were very small. The findings from this study also suggested that smaller classes are particularly beneficial for students from low socio-economic backgrounds.


Pause for thought…

So, to answer the original question, ‘Does size matter?’, the answer is for most students, yes, yet this appears to be dependent on student demographics and the academic discipline.

Smaller class sizes can have a positive effect on academic outcomes and student satisfaction, yet how feasible is it for universities to shift to smaller class sizes? Would they be prepared to do this despite the financial implications of this shift?


Perhaps the focus needs to shift away from the size of the class and focus on evidence-based learning activities that are most effective for both smaller and larger class sizes.

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