Archive

• Season's Greetings — December 30, 2011
• Class Size — November 11, 2011
• Functional School Consolidation — October 28, 2011
• Effective Professional Development — October 14, 2011
• Kindergarten Readiness — September 30, 2011
• Social Media — September 16, 2011
• Magnet Schools — August 26, 2011
• Teacher Induction Programs — August 12, 2011
• Social-Emotional Learning — July 29, 2011
• College Faculty and Student Success — July 15, 2011
• School Turnaround Models — July 1, 2011
• Language Testing and ELLs — June 10, 2011
• Math Teacher Educational Background — May 27, 2011
• Urban Inclusion Models — May 13, 2011

The Reference Desk, using available evidence and research, provides quick-turnaround responses to questions submitted by education stakeholders around the Northeast and Islands Region. Every Friday, REL-NEI highlights one or two questions submitted to its Reference Desk.

Question of the Week

What Does the Research Say About the Effect of Class Size on Student Achievement?

The Reference Desk receives many questions about school reform initiatives that impact student achievement. This week’s Digest addresses the issue of whether reducing class size affects student achievement.

Question

What does the research say about the effect of class size on student achievement?

Research Synthesis

Reference Desk researchers have found that “for the most part, research tends to support the notion that smaller classes in the early grades promote effective teaching and learning. While not all studies on the subject have shown that students learn more in smaller settings, most studies have found benefits” (Education Commission of the States, see below). A number of the debates about the impact of class size reduction have to do with methodological considerations regarding how researchers have aggregated the data in various meta-analyses of studies (Mishel, 2002; see below). One study of Tennessee's class-size experiment, Project STAR, found class size reduction positively correlated with high-school graduation (Finn, 2005; see below). Still another study suggests that students in smaller class sizes in kindergarten through grade 3 show gains in reading, language arts, and mathematics (Biddle, 2002; see below).

Publicly Available Resources

1. What Research Says About Small Classes and Their Effects. 2002; Biddle, B.J. and Berliner, D.C.; Policy Perspectives, part of In Pursuit of Better Schools: What Research Says series; 24 pages.

   This article examines various studies on class size, which include kindergarten through third grade reductions such as the Student Achievement Guarantee in Education (SAGE) program. Findings from one of the studies showed “…larger gains for students from small classes—in achievement scores for language arts, reading, and mathematics—that are roughly comparable to those from the STAR project” (p. 12). The authors presented three general conclusions regarding small classes: “When it is planned thoughtfully and funded adequately, long-term exposure to small classes in the early grades generates substantial advantages for students in American schools, and those extra gains are greater the longer students are exposed to those classes; Extra gains from small classes in the early grades are larger when class size is reduced to less than 20 students; Extra gains from small classes in the early grades are found for various academic topics and for both traditional measures of student achievement and other indicators of student success” (p. 14).

2. The Class Size Debate. 2002; Mishel, L. and Rothstein, R. eds; The Economic Policy Institute; 111 pages.

   This resource, an online book published by the Economic Policy Institute, examines the methodological issues related to the class size debate in education. From the back cover: “In The Class Size Debate, two eminent economists debate the merits of smaller class sizes and the research methods used to measure the efficacy of this education reform measure. Alan Krueger (Princeton University) maintains that smaller class sizes can improve students’ performance and future earnings prospects. He challenges Prof. Hanushek’s widely cited analysis of the class size literature, arguing that it gives disproportionate weight to single studies that include a large number of estimates. An appropriate weighting, he says, would reveal that class size is indeed a determinant of student achievement. Eric Hanushek (Stanford University) counters that Prof. Krueger’s re-analysis achieves results different from his own by emphasizing low-quality estimates. He argues that other policies besides class size reduction, such as improving teacher quality, are more important.”

3. Small Classes in the Early Grades, Academic Achievement, and Graduating from High School. 2005; Finn, J.D., Gerber, S.B., and Boyd-Zaharias, J.; Journal of Educational Psychology, Volume 97, Number 2; pp. 214-223; ERIC Document # EJ688344.

   From the ERIC Abstract: “This investigation addresses 3 questions about the long-term effects of early school experiences: (a) Is participation in small classes in the early grades (K-3) related to high school graduation? (b) Is academic achievement in K-3 related to high school graduation? (c) If class size is related to graduation, is the relationship explained by the effect of participation in small classes on students' academic achievement? The study included 4,948 participants in Tennessee's class-size experiment, Project STAR. Analyses showed that graduating was related to K-3 achievement and that attending small classes for 3 or more years increased the likelihood of graduating from high school, especially among students eligible for free lunch.”

The Reference Desk also found these organizations and their websites to be helpful in learning more about class size:

1. CSR (Class Size Reduction) Research Consortium
   

   CSR is “composed of major California research organizations working in partnership on a four-year, comprehensive study to evaluate the implementation and impact of California's class size reduction initiative under a contract with the California Department of Education. The evaluation was legislatively mandated and based on a research plan adopted by the State Board of Education. The Consortium is headed by the American Institutes for Research (AIR) and RAND and involves Policy Analysis for California Education (PACE), WestEd, and EdSource.”

2. Education Commission of the States: Class Size Reduction Issue Page
   

   “The Education Commission of the States (ECS) is an interstate compact created in 1965 to improve public education by facilitating the exchange of information, ideas and experiences among state policymakers and education leaders.” The ECS website includes an overview of class size reduction information and resources.

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