Bruce Baker responds to a Star-Ledger article reporting higher test scores for charter schools than for district public schools. His review of student population differences in Newark schools and reanalysis of 2009 test results provide the basis of his argument that because N.J. charter schools tend to serve different populations than district public schools and to have high rates of attrition, the comparisons of test scores of the two sets of schools do not provide meaningful input into the policy debate about school reform.