Frequently Asked Questions About 'California's Charter Schools: Measuring Their Performance'

June 2007

Study findings       Press release

What is a charter school?

A charter school is a public school that operates under a specific performance agreement (charter) approved by a school district, county office of education, or the State Board of Education. Charter schools are subject to fewer restrictions than are traditional public schools, but they are accountable for meeting student achievement goals specified in the charter and under state and federal accountability policies.

How many charter schools currently operate in California?

Since the Charter Schools Act was passed in 1992, the number of charter schools has grown steadily. There were 574 charter schools operating in California during the 2005-2006 academic year with a combined enrollment of 202,683 students, or 3.2 percent of all K-12 students in California.

What is the difference between a CMO/EMO-member charter school and a non-member school?

CMO/EMOs (Charter/Educational Management Organizations) are non-profit or for-profit organizations that provide administrative support and instructional leadership for more than one charter school. Some of the best-known CMOs operating in California are Green Dot Public Schools, the Knowledge is Power Program (KIPP), and Aspire Public Schools. Non-member charter schools are not affiliated with a CMO.

Does this study prove that CMO charter schools are ‘better’ than non-CMO charters?

On average, CMO members performed better academically than nonmember charters after adjusting for differences in student backgrounds and enrollment. However, this does not mean that CMO charters are better for all students in all circumstances. Student achievement on standardized tests is only one factor that makes a "good school.” Many other elements, including a school’s educational approach, the training and retention of its teachers, its facilities and resources, and the school’s ability to meet each student’s individual needs should be considered when evaluating overall school quality. Further, remember that this finding is citing averages – there were individual CMO charter schools that were not performing as well as nonmember charters, and vice versa.

How did all charter schools (regardless of CMO membership) compare to traditional public schools?

The study compared charter to traditional public school performance on achievement tests at the elementary, middle, and high school levels. It found that, on average, charter middle schools significantly outperformed noncharter middle schools on all measures. Charter elementary schools underperformed their noncharter peers on most measures. Charter high schools outperformed traditional public high schools overall, although traditional public schools generally performed better on standards-based math tests.

What does it mean to “control for school size and student background” and why is this important?

Studies have shown that academic performance at individual schools is heavily influenced by the demographic characteristics of the student body. For example, students whose parents graduated college tend to perform better on achievement tests than students whose parents did not complete high school.

The EdSource study “controlled” for many of these factors, including parental education levels, socioeconomic status, and school size. As a result of these controls, EdSource was able to compare schools on an “apples to apples” basis, ensuring that results identified were not due to underlying demographic differences between students attending different types of schools.

What is the difference between a “classroom-based” charter school and a “nonclassroom” charter school?

A classroom-based charter is a school that requires pupils to be on campus and under the direct supervision of a teacher for at least 80 percent of instructional time. Approximately 80 percent of charter schools in California are classroom-based. Nonclassroom charter schools, which include independent study programs and home school support networks, do not meet the 80 percent on-campus threshold.

What sources were used to measure student performance in this report?

The primary data sources for this report were the California Academic Performance Index (API), the California High School Exit Exam (CAHSEE), the California Standards Tests, and Annual Yearly Progress (AYP), which measures the percentage of students achieving proficiency on the state’s academic standards. For a detailed explanation of the components used to calculate the API, see this guide.

Haven’t past EdSource studies analyzed charter school performance?

This is EdSource’s third annual report on charter school performance, but it is the first time EdSource controlled for school size and student background, an important methodological improvement.

How can parents learn more about the performance of a specific school?

The Ed-Data Partnership web site—www.ed-data.k12.ca.us—provides extensive information about every public school in California, including student performance and staffing information. Information on both charter and noncharter schools is available.

What is EdSource and who funded this research?

EdSource is an independent, impartial, not-for-profit organization whose sole mission is to clarify complex education issues and to promote thoughtful decisions about public school improvement. EdSource does not advocate or lobby and has developed a solid reputation as a credible and impartial source of K-12 education information. EdSource has a multi-year grant from Reed Hastings, Founder and CEO of Netflix, Inc. and a former President of the California Board of Education, to independently analyze and report annually on charter school performance, including this 2007 report: California’s Charter Schools: Measuring Their Performance.