Abstract: California’s classroom-based charter schools were 33 percent more likely to meet student performance goals in 2004 than were regular public schools, according to this new study. Classroom-based charters significantly outperformed regular public schools and non-classroom based charters. Among schools with data available, 64 percent of classroom-based charter schools met their performance targets in 2004, compared to 48 percent of regular public schools, and 44 percent of nonclassroom-based charters. Charter schools outperformed at all grade levels. Charter elementary schools outperformed regular public schools 57 percent to 46 percent; charter middle schools outperformed regular public schools 81 percent to 54 percent; and charter high schools outperformed regular public schools 58 percent to 49 percent. Charter school age did not significantly affect performance.