91ÖÆƬ³§ÊÓƵ

How We Graded the States

For the print edition of Quality Counts 2014, the 91ÖÆƬ³§ÊÓƵ Week Research Center graded the states in two critical performance and data categories, the K-12 Achievement Index and school finance. Due to a delay in the release of U.S. Census Bureau data caused by the recent government shutdown, new results for the Chance for Success Index were not available for inclusion in the report’s print edition. Updated grades for that category are only available online and in the State Highlights Reports. These three sections are comprised of 39 distinct indicators based on original analyses of state and federal data.

Best-in-Class Grading

The Chance for Success Index, K-12 Achievement Index, and school finance are scored using a best-in-class rubric. Under this approach, the leading state on a particular indicator receives 100 points, and other states earn points in proportion to the gaps between themselves and the leader.

This calculation is straightforward for indicators with a clearly bounded measurement scale. Examples of such indicators include the zero-to-100-point scale for the percent of students proficient in reading, or states’ per pupil expenditures expressed in positive dollar amounts.

But some of the indicators—such as those related to the equity of education spending—use more-complex scales for which minimum or maximum values are not as clearly defined. For such indicators, we evaluate a particular state based on its performance relative to the minimum and maximum values on that indicator. Those indicators are scored on a 50-point base, meaning that all states start with 50 points rather than zero.

To compute a state’s score for a given category, we average points across the applicable set of indicators. On a best-in-class scale, a state’s overall score for a category can be gauged against an implicit standard where 100 points would correspond to a state that finished first in the nation on each and every measure.

The Grading Scale

Using the scoring rules already described, each state receives a numerical score for each of the indicator categories. After rounding scores to the closest whole-number values, we assign letter grades based on a conventional A-F grading scale, as follows:

A = 93 to 100
A-minus = 90 to 92
B-plus = 87 to 89
B = 83 to 86
B-minus = 80 to 82
C-plus = 77 to 79
C = 73 to 76
C-minus = 70 to 72
D-plus = 67 to 69
D = 63 to 66
D-minus = 60 to 62
F = Below 60