Abstract: Charter middle and high school students in California scored higher on state assessments than their public school peers, even after factoring in school size and student background, according to this report. Charter elementary schools showed generally lower performance than traditional public elementary schools. Charter schools run by management organizations, such as KIPP, Green Dot, and Aspire, tended to perform far better than other charter schools. The study examined the 2005-06 test scores of 346 charter schools and 7,122 traditional public schools and compared schools with similar sizes, levels of parent education and rates of students receiving a subsidized lunch, among other factors.