Comparing Michigan’s public school accountability system to other states demonstrates that it is possible to craft such a system that both follows federal guidelines and is not as highly correlated with school poverty levels. In fact, of the eight states surveyed for this analysis, Michigan’s school ranking had the strongest correlation to student poverty. Some of these states’ ranking systems have been criticized by politicians and major newspapers for their association with poverty rates, even though these states’ report cards have a much lower correlation than Michigan’s report card.[29]
Arizona’s accountability system is an example of one that meets federal guidelines and has a relatively limited relationship to school poverty rates. It scores schools based on a combination of broad, overall student academic outcomes (including student pass rates on state exams and graduation rates), learning gains for all students and learning gains made by just the lowest-scoring 25 percent of students in each school.[30] Although this seems similar to the formula used for Michigan’s TTB list, the portion of students eligible for free lunches in Arizona schools explained only about 12 percent of the variation of scores for the 2012-2013 school year. Data from previous years yielded similar results.
Graphic 3 shows scores of Arizona schools based on that state’s school accountability model plotted against the percentage of students eligible for a free lunch in those schools.[*] The spread of school scores shows that Arizona rankings are less correlated with student poverty, and the slightly sloping line shows that the “penalty” for having more students in poverty is less severe than in Michigan (see Graphic 2).
Graphic 3: Arizona School Percentile Ranking and Percentage of Students Eligible for a Free Lunch, 2012-2013
Graphic 4 shows all eight states surveyed and the coefficient of determination of each state’s ranking to the percentage of students eligible for free lunch. This value shows just how much of the variation in individual school scores can be explained by the level of student poverty within each school. State school ranking data were paired with 2010-11 data on National School Lunch Program enrollment from the National Center for Education Statistics.[†]
States are listed in order of their school ranking’s relationship to student poverty, with the largest correlations on top. As is apparent, Michigan has the strongest relationship between student poverty and school rankings. Florida is the next highest, with student poverty explaining 47 percent of the variance of school scores in the Sunshine State. Arizona’s school rankings have the weakest relationship to school poverty and the relationship is consistent over time.
Graphic 4: School Accountability Systems
and School Poverty Rates
State |
School Year |
Percent of Ranking Explained by Poverty (R2) |
Michigan |
2012-13 |
55% |
|
2011-12 |
56% |
|
2010-11 |
61% |
Florida |
2012-13 |
47% |
|
2011-12 |
47% |
Wisconsin |
2011-12 |
42% |
Oklahoma |
2011-12 |
35% |
Ohio |
2011-12 |
35% |
|
2010-11 |
35% |
Maine |
2011-12 |
32% |
Indiana |
2011-12 |
30% |
Arizona |
2012-13 |
12% |
|
2011-12 |
13% |
|
2010-11 |
11% |
Source: See “Appendix A: Data Sources: School Accountability Systems and School Poverty Rates”
[*] Arizona school scores were converted to percentage top-to-bottom rankings for a clearer visual comparison to Michigan.
[†] For states with multiple years of school rankings data, the use of older student socioeconomic datasets appears to make little difference. Both Michigan and Florida saw the correlation to student poverty of their school ranking systems barely change across years when paired with newer student socioeconomic data. "Elementary/Secondary Information System," (National Center for Education Statistics, 2013), http://goo.gl/ED34jG (accessed Sept. 10, 2013).