Distribution of School Achievement. Notes: For panels A–D, the dots indicate the average of the dependent variable (Math or Reading achievement) for schools at 1 percentage point intervals (bins) of school achievement. For panels E–H, the dots indicate the proportion of students proficient in math or reading for schools at 1 percentage point intervals (bins) of school achievement. School Achievement is the running variable and represents the share of students meeting or exceeding state standards on the 2004 ISAT composite measure. The dependent variables in panels A–D are regression-adjusted average school performance (net of student-specific characteristics) measured in standard deviation units. The dependent variables in panels E–H are the proportion of students in each school meeting or exceeding Illinois state standards in math or reading. The solid lines are locally weighted regressions of the dependent variable on the running variable. The vertical line represents the estimated achievement threshold—55 percent of elementary students meeting or exceeding state standards.