RALEIGH – If you follow state politics for any length of time, you hear some version of the following assertion: North Carolina may not rank highly in elementary and secondary education, but we make up for it by having one of the best public university systems in the United States.

Politicians may file these claims in a folder labeled “too good to check,” but I don’t possess such a folder. Every political claim is worth checking. And these claims don’t check out very well.

There are actually two parts to the argument. The first is that North Carolina doesn’t rank well in public education among the 50 states. The second is that North Carolina ranks highly in higher education among the 50 states. Let’s take them in turn.

In K-12 public schools, North Carolina is hardly at the bottom of the national list in outcomes. In math, North Carolina 8th graders had an average score on the National Assessment of Educational Progress (NAEP) of 286 in 2011, vs. 283 for the nation as a whole. Measured a different way, 37 percent of North Carolina 8th graders were proficient in math, vs. the national average of 35 percent.

On the 2011 NAEP reading exam, the North Carolina average score was 263 with a proficiency rate of 31 percent, vs. a U.S. average of 264 with a proficiency rate of 34 percent. On the latest NAEP science exam, in 2009, the North Carolina average score was 144 with a proficiency rate of 24 percent, vs. a U.S. average score of 150 with a proficiency rate of 29 percent.

In sum, North Carolina is a bit above the national average in math, not statistically different from the national average in reading, and a bit below the national average in science. And our graduation rate of 75 percent in 2008-09 was just slightly below the national rate of 75.5 percent. As I noted yesterday, North Carolina’s real K-12 problem is that being average in America means being below average in international comparisons.

Now let’s turn to the second part of the argument: that North Carolina has a superlative ranking in higher education. Certainly the state of North Carolina subsidizes its public colleges and universities to a greater extent than nearly every other state in the nation. Tuition and fees pay for only about a fifth of the total University of North Carolina budget. If we exclude from that total budget all research, public service, auxiliary enterprises (such as hospitals) and capital costs, tuition covers about 50 percent of direct student expenses in the UNC system – vs. the national average of 91 percent.

But our higher level of subsidy doesn’t translate into higher levels of college attainment or workforce productivity. North Carolina ranks slightly below the national average in the share of adults with bachelor’s degrees, 26 percent vs. 28 percent. We enroll large numbers of students at taxpayer expense, but at only two campuses – UNC-Chapel Hill and the N.C. School of the Arts – do most students complete their degrees in four years. In fact, fewer than 60 percent of students across the UNC system graduate within six years.

And while there is no higher-education equivalent to the NAEP to provide objective comparisons of student learning across the country, the available evidence suggest that North Carolina taxpayers are not getting a solid return on investment even for those who do graduate. Last month, Bloomberg Businessweek released a study of return on investment for colleges and universities. The researchers computed average 30-year earnings for the alumni of each school, subtracted the cost of obtaining their degrees, and then compared the result to the average earnings of high-school graduates.

Among state university systems, North Carolina ranked a disappointing 42nd in return on investment. Graduating from N.C. State, UNC-Chapel Hill, and UNC-Charlotte generated moderate-to-strong returns, but for many other campuses the returns was low, and in a few cases negative. In short, we are admitting many students to UNC campuses who are not truly ready for college-level work. Some never graduate. Others graduate with degrees that don’t prove particularly valuable in the job market. For both groups, the large subsidy for their education has not generated economic benefits either for themselves or state taxpayers. (These students may derive social or other benefits from going to college, of course, but the case for forcing taxpayers to subsidize those benefits is rather weak.)

So the next time you hear someone claim that North Carolina lags the nation in K-12 education and leads the nation in higher education, ask him to back up his claim with actual facts, not conventional wisdom.

Hood is president of the John Locke Foundation.