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School class sizes are a hot-button issue. On the eve of the new school year, the C.D. Howe Institute issued a commentary on school class size in which it argues “small isn’t better.” The Globe and Mail responded with an editorial favouring smaller class sizes. The volley between the Globe and C.D. Howe is just the most recent skirmish in a debate that has raged for decades.
Few topics generate as much vigorous debate as class size. Parents seeking the best conditions for their children are typically ardent supporters of small class sizes. So, too, are teachers for whom class sizes are a workload issue and a factor affecting student learning. School principals are less sanguine. The reaction from school board officials, trustees, and policy-makers conscious of the costs of reducing class sizes ranges from sceptical to hostile. The debate has raged for more than a half century and has provoked bitter divisions between proponents and opponents.
Class size refers to the specific number of students enrolled in a particular teacher’s classroom. Pupil-teacher ratio refers to the total number of students enrolled in a school (or district) divided by all of the teachers in the school (or district). Schools typically have instructional staff members who do not manage a classroom grouping of students. A school’s librarian, the vice principal and principal, and teachers who provide support outside a classroom for learners facing challenges also count as teachers for the purpose of determining the pupil-teacher ratio of a school or school district. There is a vast difference between the number of students a teacher instructs each day (class size) and the total number of students in a school divided by the total number of teachers working in that school in teaching, administrative and educational support functions.
Everyone concerned about student learning has asked at one time or another: What, if any, are the benefits of small classes? Educational researchers Bruce Biddle and David Berliner (2002) undertook a broad examination of research into class size from a variety of investigative traditions – small field studies, surveys, econometric studies and large field experiments – and explained their contributions, strengths and limitations. Based on their review of research from a variety of sources addressing a vast landscape, they conclude that:
While it is unlikely to quell the passions the topic has engendered, research can shed some light on the controversy and inform the decisions that school officials and policy makers must make. Research can tell us the cost of a given effect produced by changes in class size and enable a comparison of the costs and benefits of alternative means of achieving a common outcome such as improved reading or mathematics achievement.
The results of research investigating such matters as the impact of class size on student achievement can be expressed in an effect size. The effect size tells how much increase or decrease in student achievement can be attributed to changes in class size, expressed in standard deviation units. Using such information, the cost of achieving a particular result can be calculated by linking the cost of making the changes to the given effect size. They could also compare the costs of other changes that produced similar effect sizes.
To illustrate, Levin (1984) and his colleagues combined research synthesis techniques and cost-effectiveness instruments to compare the cost-effectiveness of four educational interventions to improve elementary mathematics and reading achievement: cross-age tutoring, computer-assisted instruction; class size reductions, and increases to instructional time. Although the study is twenty years old, it provides an example of how one can assess the cost-effectiveness of such practices as class size by calculating the size of the effect achieved per $100 cost per student.
Table one from Statistics Canada contains the ratio of students to educators in public schools across the nation. The student/educator ratio is Canada’s equivalent of the pupil-teacher ratio. The ratio of students to educators is typically lower than the actual class sizes reported by the provinces and territories. For example, in the most recent data available from Newfoundland, that jurisdiction reports that, in 2004-05, class sizes from kindergarten to grade three averaged 18.3; in grades four to six, the average was 20.9; and in grades seven to nine, the average was 23.3. At the other end of the country, BC reported that, in 2004-05, its average class size from kindergarten to grade 7 was 23.2.
BC’s School Act directs school boards to ensure that, in the aggregate, the average size of kindergarten classes is 19 students, 21 students for grades one to three, and 30 students for grades four through 12. Cognizant that aggregate averages could mask significant variation in size, BC’s School Act requires that kindergarten classes do not exceed 22 students in any given class and 24 students in grades one to three. What these figures make clear is that there is a vast difference between the student enrolment in a teacher’s class and the ratio of the total number of students in a school, district or province to the total number of teachers or educators. Unless a clear distinction is made between the two, it was difficult to interpret research results correctly.
Class size is arguably the most frequently investigated issue in education in developed countries around the world and one of the most contentious as well. It is surprising that, despite the volume of research and the debate it engenders, there is comparatively little class size research in Canada and only limited research that seeks to compare the cost-benefit ratio of educational interventions such as class size aimed at improving student success. Despite the small volume of Canadian research, many Canadian jurisdictions have articulated and implemented policies regarding class size.
In some jurisdictions (Yukon is one example) class sizes are determined by a collective agreement between the Yukon Government and the Yukon Teachers’ Association. In that jurisdiction, class size maximums are set at 20 students for kindergarten; 23 students in grades one to three; 26 students in grades four to nine; and 28 students in grades 10 through 12. In home economics and industrial education classes (classes where safety is a factor), class sizes have been set at 16 students per class.
In other jurisdictions, class size limitations or reductions are set by public policy rather than collective bargaining. For example, Ontario is pursuing class size reductions as part of its efforts to improve student literacy in the primary grades. In May 2005, Ontario’s Premier, Dalton McGuinty, said, “We want all of our children to get the individual attention they need to succeed in the important early grades.” According to Ontario’s Minister of Education, plans are on track to ensure that there are no more than 20 students in any junior kindergarten to grade three class in the province by the 2007-2008 school year.
Alberta’s government committed itself to reducing class sizes by 2006-2007 across the grade range. It plans an average of 17 students from kindergarten to grade three; 23 students from grades four through six; 25 students from grades seven to nine; and 27 students from grades ten through twelve. Nova Scotia, like Ontario, has limited its class size initiative to the early years.