Senior Education Officer
November 19, 2012
By Steve Benton
During the third and final 2012 presidential debate the topic of class size came up within the context of global competitiveness. Putting aside political views, the question of how class size affects teaching and learning is worth considering. So, I decided to do some quick analyses of IDEA student ratings collected in 490,196 classes from 2002 to 2011 to see whether differences exist by class size on some key items.
Instructors in large (35-49) and very large classes (50+) were more likely to emphasize gaining factual knowledge, whereas those in small (10-14) and medium-sized (15-34) classes put more emphasis on developing communication skills (both oral and written). Instructors in small classes also reported better student preparation, student enthusiasm, and effort than those in large and very large classes. Finally, instructors in small and medium classes required more writing, oral communication, and creative/artistic design.
With respect to students, the smaller the class the higher was students’ achievement and overall impressions of the course. There was a consistent class-size pattern of small > medium > large > very large for student progress on relevant objectives (i.e., those the instructor identified as either essential or important for the course). Smaller classes were especially well suited for developing students’ creative capacities and oral and written communication skills. The same pattern existed for the three overall summary measures of attitudes toward the field of study, excellence of the teacher, and excellence of the course.
Next, I looked at course and student characteristics. A case can be made that students in smaller classes perceive their course as more rigorous. Across all 10 years of data, students in small and medium classes reported a greater amount of reading and non-reading assignments in their classes than those in large and very large classes. Moreover, the pattern of small > medium > large > very large was repeated for ratings of the instructor’s achievement standards and expectations that students take their share of responsibility for learning. In spite of that greater rigor, students in small classes consistently reported a stronger desire to take the course and stronger work habits than those in larger classes.
These results are not surprising. The IDEA Center has known for years that class size makes a difference, which is why course enrollment has long been one of the items used in the adjusted scores. Moreover, recommended actions presented on Page 3 of the Diagnostic report are made based on comparisons between the class’ average rating for a teaching method and other classes of similar size. The effectiveness of a teaching method depends not only on which objective is being emphasized but also on how many students are enrolled in the course.
Therefore, with respect to student ratings of learning, teaching, and the course, class size matters.