Click here for the full study.
Assessing a high school’s effectiveness is not straightforward. Comparing a
school’s standardized test scores to those of other schools is one approach to
measuring effectiveness, but a major objection to this method is that students’
test scores tend to be related to students’ “socioeconomic” status — family
household income, for example, or parents’ educational background. These
factors, however, are outside a school’s control.
The Michigan Public High School Context and Performance Report Card is an
attempt to provide a better “apples-to-apples” comparison of public high schools by adjusting their students’ average standardized test scores to account for disparities in the socioeconomic status of their student populations.
Socioeconomic status in the Context and Performance (“CAP”) Report Card
is measured by the percentage of a school’s students who qualify for a free or
reduced-price lunch under the federal government’s National School Lunch
Program. The standardized tests used in the report card are from the Michigan
Merit Examination — including the ACT® test — taken by the schools’ 11thgraders
from 2008 through 2011.
We used regression analysis to measure the relationship between student test
results and subsidized-lunch counts in Michigan’s general education public high
schools (schools focused on special education or alternative education were
excluded from our analysis). We then determined whether each school’s student
population performed better or worse than projected based on the school’s
The resulting “CAP Score” for a school was above 100 if the school exceeded
its projected performance and below 100 if the school fell short (the statewide
average CAP Score was set at 100). Grades were assigned using a standard bell
curve, with 10 percent of the schools receiving an A, 20 percent receiving a B,
40 percent receiving a C, 20 percent receiving a D and 10 percent receiving an F.
It is important to remember that these CAP Scores and grades are relative.
Each high school is assessed based on its performance compared to other high
schools in the state; CAP Scores do not indicate how well these high schools
compare to those in other states or countries. Moreover, CAP Scores do not
adjust for every factor that may lie outside a school’s control. Nevertheless, by accounting for a major factor that is substantially related to student achievement and outside a school’s control, the CAP Report Card improves the quality of information publicly available to Michigan parents, taxpayers, school officials and policymakers.
Click here for a PDF of the study.