California's Academic Performance Index (API) is the state's main accountability metric. Authorized by the Legislature in 1999, around the time California was implementing rigorous new standards in math, science, social studies, and English language arts, the API relies heavily on the results of standardized tests designed to align with those standards. In "Measures That Matter: Why California Should Scrap the Academic Performance Index," Richard Lee Colvin takes an in-depth look at how well the API is working. His answer: not very well. The API has problems that were known from the beginning. It is, "to a large extent, an indicator of students' wealth rather than of a school's educational quality." It places overwhelming emphasis on math and reading, which results in an under-emphasis on science and social studies. And because more than 40 percent of California schools have API scores at or above the state minimum, they no longer have to worry about helping students who are not yet proficient reach that goal. That means that schools that enroll more affluent and better performing students could rest on the laurels of their students and let the quality of teaching slide. Now is the time to fix those problems, says Colvin. The current policy context presents California with an opportunity to make significant changes that for several reasons might be less possible later on. First is what Colvin calls NCLB's "looming deadline," the date by which all students are supposed to achieve proficiency in math and English. Already, more than 2,500 California schools have failed to achieve their goals for seven years. At a minimum, these schools should be pressured to make changes. Second, the impending shift to Common Core assessments offers further opportunity for a change. Some states are viewing this change as an opportunity to shift to a system that relies more heavily on student growth. "Both the API, and a new measure, could continue to be reported," says Colvin. "The low-stakes pilot would allow the state to iron out any bugs that occurred, as is being done in Los Angeles." (Contains 34 notes.)