The Teachability Index: Can Disadvantaged Students Learn?

Student “teachability”—the personal advantages and disadvantages that students bring to school with them—plays an important role in public discussion of education policy. Huge increases in resources are producing no improvements in student achievement: inflation-adjusted spending per pupil has doubled in the last thirty years while academic outcomes are flat. Defenders of the status quo claim the reason is that students are less teachable than they used to be; problems like poverty and social dysfunction have made the schools’ job harder. They also claim that systematic reforms like school choice and accountability testing won’t help, because students with low teachability levels can’t be expected to learn better even with reforms unless the disadvantages that students bring to school are also addressed.

These claims are rarely subjected to serious scrutiny. This study, the first of its kind, systematically measures the teachability of students by examining sixteen social factors that researchers agree affect student teachability. Combining these factors into a single Teachability Index provides the first-ever valid measurement of whether schools are facing a student population with greater challenges to learning.

The Teachability Index shows that students today are actually somewhat easier to teach than they were thirty years ago. Overall, student disadvantages that pose challenges to learning have declined 8.7% since 1970. Children’s physical health and economic security have substantially improved, and preschool enrollment has grown dramatically. While other factors have presented increased challenges—broken homes and students whose native language isn’t English are more common—these changes have been more than offset by ongoing improvements in children’s well-being. This means that student teachability cannot be a valid excuse for the failure of vastly increased spending to produce better results (see Figures 1a–1c).

The states with the highest scores on the Teachability Index were North Dakota, Maine, New Hampshire, Vermont, and South Dakota. These states had student populations with the lowest levels of disadvantages that present obstacles to learning, as well as the highest levels of advantages. The states with the lowest scores on the Teachability Index were Louisiana, Texas, Arizona, New Mexico, and the District of Columbia.

We also compare the teachability levels of students in each state with their academic outcomes. The School Performance Index gives the level of student achievement in each state expressed as a percentage of the level that would be predicted by the teachability of its students. We find that some states with low student teachability perform much better than their students’ problems would lead us to expect, while other states do not rise to this challenge (see Figure 10). This indicates that what schools do still matters even when students are facing obstacles to learning.

In particular, states with more school choice or stronger accountability testing demonstrate better school performance. Our statistical analyses find significant relationships between both of these reforms and the School Performance Index, meaning that these reforms produce higher levels of student achievement relative to student teachability.

The states with the highest scores on the School Performance Index were Montana, Colorado, Kansas, Texas, and North Carolina. Students in these states had the highest levels of academic achievement relative to their teachability—that is, these states had actual achievement levels that were the furthest above the levels we would expect to see, given the disadvantages that students faced. The states with the lowest scores on the School Performance Index were California, Alabama, Mississippi, Hawaii, and the District of Columbia.

Finally, we calculate a School Efficiency Index to determine which states are getting the best results for their education dollars. This index gives the level of student achievement in each state expressed as a percentage of the level that would be predicted by the teachability of its students and its level of education spending. We find that some states get substantially more education for each dollar they spend (see Figure 12).

The states with the highest scores on the School Efficiency Index were Utah, Idaho, Oklahoma, Kentucky, and Arkansas. Students in these states had the highest levels of academic performance relative to their teachability and the states’ education spending—that is, these states had actual achievement levels that were the furthest above the levels we would expect to see, based on their students’ teachability and their spending. The states with the lowest scores on the School Efficiency Index were Alaska, New York, Connecticut, New Jersey, and the District of Columbia.

This study indicates that teachability cannot serve as an excuse for the education system’s failure to perform, and it provides evidence that student disadvantages are not destiny: some schools do much better than others at educating students with low levels of teachability.

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