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Class Size Does Matter

California had the largest class sizes in the nation in 2007-08, with an average 50 teachers per 1,000 students. Every budget cut of $1 billion statewide is equivalent to raising class sizes by 5%.

Research Shows that Class Size Reduction Improves Student Achievement, Particularly for Students with Greatest Needs

• There is clear evidence that smaller class sizes raise student achievement, and the positive effect is even more prominent in schools serving predominantly low-income students.

• California’s K-3 Class Size Reduction Program demonstrated that class size effects held up across a wide spectrum of students of different ethnic, economic, and language backgrounds.

• California’s Class Size Reduction Program has led to significantly better scores by students on National Assessment of Education Progress (NAEP) exams. One study shows that between 1996 and 2000, California 4th graders’ NAEP scores in Mathematics increased.

• Research proves smaller classes improve student learning. According to a June, 2002 study by the Public Policy Institute of California, five of the state’s largest school districts reported significant test score gains since the state’s class size reduction program began. Third-grade test scores increased 14% in math and 9% in reading in schools with mostly low-income students.

• The official evaluation of Wisconsin's SAGE CSR program found that smaller classes increased student achievement, upheld the gains through 3rd grade, and narrowed the achievement gap between African-American students and white students.

• A recent international study, which included reviews of CSR programs in the United States, Great Britain and Hong Kong, found that smaller classes can benefit all pupils in terms of individual, active attention from teachers, and that lower-achieving students in particular can benefit from smaller classes at the high school level.

• Smaller classes benefit all students, but also help close the achievement gap – improving scores for African-American students by nearly 40% in one study.

• A study of the long-term effects of Tennessee’s K-3 class size program, Project STAR, found that smaller classes increased high school graduation rates, especially among students eligible for free lunch.”

Other Benefits of Class Size Reduction Programs

• “Class size reduction is widely popular with parents and school staff, many of whom report marked improvements in classroom learning environments and working conditions for teachers.”

• In a 2007 poll of American’s views on public education, 95% of respondents called smaller classes a very effective way to attract and retain public school teachers, ranking it higher than all other options surveyed, including pay incentives and more professional development opportunities.

• Smaller class sizes have also improved future job earnings for millions of students.

• A cost-benefit analysis of the STAR project in Tennessee estimated that reducing class sizes from 22 to 15 in grades K-3 resulted in a $2 return on every $1 spent.

• The Class Size Reduction Research Consortium recommended that California better serve at-risk students by focusing full CSR funding on the districts with the most challenging schools, thus providing an incentive to draw the best-qualified teachers to those schools. The CTA-sponsored Quality Education Investment Act of 2006 has targeted its class size reduction efforts at California’s schools of greatest need for this very reason.

Facts – Sources:

National Education Association, Rankings & Estimates, 2008-09 (2007-08 data). K-12 Students in ADA, FTE public school teachers.

In 2007-08, California had a ratio of 50 teachers for every 1,000 students (300,500 FTE teachers teaching over 6 million students). A cut of $9.7 billion would equate to laying off 138,571 teachers ($9.7 billion, divided by average teacher salary & benefits of $70,000). The result would reduce California to a ratio of 27 teachers for every 1,000 students (161,929 FTE teachers after layoffs, teaching the same over 6 million students). This represents a 50% increase from 2007-08 (50-27 ÷ 50 = 46%).

Research – Sources:

Jepsen, Christopher, Rivkin, Steven, Class Size Reduction, Teacher Quality and Academic Achievement in California Public Elementary Schools, PPIC, 2002.

Bohrnstedt, G.W., et. al. “The California class size reduction evaluation: Lessons learned,” in How Small Classes Help Teachers to Do Their Best, M.C. Wang and J.D. Finn (editors), Temple University Center for Research in Human Development in Education, 2000.

Unlu, Faith, California Class Size Reduction Reform: New Findings from the NAEP, Princeton University Department of Economics, November, 2005.

Jensen, Christopher and Rivkin, Steven, “Class Size Reductin, Teacher Quality, and Academic Achievement in California Public Elementary Schools,” Public Policy Institute of California, 2002.

Smith, Philip, Molinar, A., and Zahorik, John A., Class Size Reduction in Wisconsin: A Fresh Look at the Data, Education Policy Studies Laboratory (EPSL-0309-110-EPRU), September, 2003.

Blatchford, Paul Bassett, and Brown, Penelope, University of London School of Psychology and Human Development, Institute of Education, Do Low Attaining and Younger Students Benefit Most from Small Classes?, paper presented at the American Education Research Association’s annual conference, 2008.

Krueger, Alan B., Would Smaller Classes Help Close the Black-White Achievement Gap?, Princeton University, Industrial Relations Section, Working Paper #451, March 2001. “Small Classes in the Early Grades, Academic Achievement, and Graduating from High School,” Journal of Educational Psychology, 2005, Vol. 97, No. 2, 214-223.What We Have Learned About Class Size Reduction in California, CSR Research Consortium Capstone Report, September, 2002.

Rose, Lowell C. and Gallup, Alec M., “The 39th Annual Phi Delta Kappa/ Gallup Poll Of the Public's Attitudes Toward The Public Schools, 2007. [http://www.pdkintl.org/kappan/k_v89/k0709pol.htm]

Krueger, Alan B., Princeton University Department of Economics, The Class Size Debate, Economic Policy Institute, 2002.

Kruger, Alan B., “Economic Considerations and Class Size,” Economic Journal, vol. 113, pp. 34-63, 2003. What We Have Learned About Class Size Reduction in California, CSR Research Consortium Capstone Report, September, 2002.

Revised January 2009

Every child deserves a chance to learn and no child succeeds alone.

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