Evidence Shortage for Teacher Shortage

October 28, 2015

Andrew J. Coulson

According to recent news reports, many states are facing a teacher shortage. This is said to be proven by a Google search returning blog posts and news stories in which some people claim there is a teacher shortage. But is that true? The claimants could be uninformed, misinformed, or even have incentives to cry “shortage!” when there isn’t one. For instance, consider this U.S. government program for cancelling teachers’ loans:

34 CFR 674.53(c) enables Federal Perkins Loan borrowers who are full-time teachers of mathematics, science, foreign languages, bilingual education or any other field of expertise where the State educational agency determined there is a shortage of qualified teachers to qualify for cancellation of up to 100 percent of their loan repayment.

Hmm. But let’s not speculate. The federal government’s National Center for Education Statistics compiles data on public school enrollment and teacher employment. To verify the claims of teacher shortages nationally and in Indiana, for example, I charted the data in the figure below. [OCPA economist Scott Moody has created a similar chart for Oklahoma at the bottom of the article.]


For the United States as a whole, we see that there are fewer pupils per teacher today than at almost any time in the past 50 years. Put the other way, we currently have more teachers per pupil than we’ve had in the past—with the exception of a brief period last decade.

In the case of Indiana, the pupil/teacher ratio is about the same as it was in 1982. The difference between Indiana’s ratio and that of the nation as a whole is currently less than one student/teacher.

Clearly, the nation has been on a very long teacher-hiring binge. Since 1970, the number of teachers has grown six times faster than the number of students. Enrollment grew about 8 percent from 1970 to 2010, but the teaching workforce grew 50 percent. There are a lot more public school teachers per child today, so how can districts and states still claim to be facing “teacher shortages”?

In some areas, the shortages are said to be restricted to teachers of certain subjects or grade levels. But if that is so, it only begs the question: why did the system hire so many teachers in the other subjects where there were not shortages—decade after decade? Wouldn’t it have been wiser not to hire so many new teachers over the last 50 years in the other subjects that were not facing shortages? Had the nation not gone on what seems to be an across-the-board teacher hiring binge since 1970, districts would have more money at their disposal today to offer teachers in truly hard-to-fill positions.

As my erstwhile colleague Marie Gryphon has noted, there are “large differences among teachers in their impacts on achievement, and … high-quality instruction throughout primary school could substantially offset disadvantages associated with low socioeconomic background. [….] The group noted that good teachers matter more than smaller class sizes. Rivkin and his colleagues found that raising teacher quality by one standard deviation would improve student achievement more than a very expensive class-size reduction of 10 students per class.”

And not only have U.S. public schools favored quantity over quality in their long-term hiring behavior, they have been found to make systematically poor choices among the available candidates:

Ballou found that administrators were no more likely to hire high-ability teaching candidates than candidates of lower tested ability. He writes: “Applicants from better colleges do not fare better in the [public school teacher] job market. Indeed, remarkably, they do somewhat worse.” That was the case despite substantial evidence that higher tested ability of teachers is one of the most reliable indicators of superior classroom performance. [Gryphon 2006, italics added]

Research shows that the brighter candidates are likely to become better teachers, but also that they are less likely to be hired by public school districts in the first place.

Another respect in which the nation’s public school systems invite teacher shortages upon themselves in high-demand subjects is their erection of barriers to entering the teaching profession. States generally require candidate teachers to obtain a 4-year degree from a state-accredited teachers’ college. These credentials tend not to be portable between states. Nor, as Gryphon reported, have state teacher credentials been shown to confer a meaningful benefit on students.


The desire to drive up teacher quality is worthy, but there are more empirically supported ways of doing so. One is competition. Gryphon writes that “schools subjected to competition hire more teachers who have the specific qualities that have been tied to performance by past research: high tested ability and experience with math and science.”

So does America have a “teacher shortage” writ large? No. We had 22.3 pupils/teacher in 1970 and 16 pupils/teacher in 2012. Compared to the past, we are rolling in teachers. If we have too few in some fields and too many in others, it is for the reasons described above—mistakes in policy and/or execution. In Indiana, for example, the ratio went from 17.5 to 17.4 over the past 30 years. If there are subject-specific shortages, they are the result, again, of policy and execution.

Andrew J. Coulson is a senior fellow in the Center for Educational Freedom at the Cato Institute. He serves on the Advisory Council of the E.G. West Centre for Market Solutions in Education at the University of Newcastle, UK, and has contributed to books published by the Fraser Institute and the Hoover Institution. This article first appeared August 23, 2015, on the website of the Cato Institute.