EAST LANSING, Mich. — It’s widely believed that smaller, more intimate, class sizes are better suited for student learning than larger classes. However, a new long-term study on math and science teaching trends finds that smaller class sizes don’t necessarily always lead to higher grades and achievements. Ultimately, the research team say, the effect of class size on student performance is dependent upon a number of additional factors such as country, the subject being taught, and various cognitive and non-cognitive skills.
It’s easy to understand why most believe smaller classes are the way to go. Fewer students in each class facilitates more individualized attention from teachers, and makes it easier for administrators to maintain a sense of control. Due to these reasons, various countries have instituted limits on how large classes can be, with many capping the number at around 30 students per class.
Still, prior research on this topic has largely yielded inconsistent findings, with some studies identifying clear benefits to smaller classes, while others haven’t. Furthermore, most of this research was small in scope, focused primarily on only math or reading, and failed to consider the influence class size has on other non-academic or cognitive skills such as overall interest in the topic being taught and attentiveness.
So, in an effort to perform a comprehensive analysis on classroom size and subsequent learning, the research team used data originally collected via the Trends in International Mathematics and Science Study (TIMSS). Since 1995, every four years the TIMSS has collected performance and achievement information on fourth grade (ages 9-10) and eighth grade (ages 13-14) students from all over the world (50 countries) in math and science. Besides the nuts and bolts of letter grades, the TIMSS also recorded each participating student’s self-reported interest and attitude towards the two subjects, as well as class size information.
Of course, with a sample of data that large and extensive, the research team were forced to narrow their analysis a bit in order to make it more manageable. They ended up limiting the scope of the study to four European countries: Slovenia, Romania, Lithuania, and Hungary. While those choices may seem random at first, those four nations were chosen specifically because they all have set maximum class sizes for their schools. Even after narrowing their data, the study still included 4,277 pupils from 231 classes spread across 151 schools, making it the largest study on classroom sizes by a wide margin. This study was also the first ever to separate scientific subjects for analysis, including biology, chemistry, etc.
After finishing their investigation, researchers noted that smaller class sizes seemed to benefit students in Romania and Lithuania, but not pupils in Slovenia or Hungary. Romanian students saw the biggest benefits, with smaller classes being associated with better grades in math, chemistry, earth science, and physics. Romanian students even seemed to enjoy learning math more within smaller classes. Lithuanian students, on the other hand, enjoyed learning scientific subjects more in small classes. Across all of these observations, though, the benefits were only observed in certain years.
“Most class size effects were not different than zero, which suggests that reducing class size does not automatically guarantee improvements in student performance,” says study author professor Spyros Konstantopoulos of Michigan State University in a release. “Many other classroom processes and dynamics factor in and have to work well together to achieve successful outcomes in student learning.”
The study’s author theorize that Romania and Lithuania saw greater benefits from smaller classes because they generally have poorer school funding and fewer resources than Hungary or Slovenia.
“This finding is perhaps due to the fact that class size effects are more likely to be detected in countries with limited school resources where teacher quality is lower on average,” professor Konstantopoulos explains.
The study is published in the scientific journal Research Papers in Education.