The Impact of Milwaukee Charter Schools on Student Achievement: A recent report from the Brookings Institution presents panel data analyses using student fixed effects models to estimate the impact of Milwaukee charter schools on student achievement. The report finds that attendance at a charter school is associated with small positive increases in math test scores and with no significant differences in reading scores. The positive effects estimates for math are largely limited to earlier years of the charter school program and to gains made during the first year in a charter, and the results might be dependent on the study’s approach to modeling transfers between schools. The review identifies several questions about the internal and external validity of the reported estimates. Nevertheless, the methods used in the study do have important strengths. When the results are considered together with the large body of research on charter schools, the conclusion that charter schools should not be expected to have large effects on achievement in urban schools is reasonable.