Speaking after Ben Carson endorsed him for president March 11, Donald Trump praised Carson's expertise on education. (Reuters)

You thought Ben Carson was an expert in neurosurgery, because he is, well, a world-renowned neurosurgeon. But, it turns out, he is also an education expert, or so says Donald Trump, who just welcomed Carson’s endorsement for the Republican presidential nomination and declared that Carson was going to help him with education issues because he knows so much about them.

At a news conference on Friday, Trump said that he spent some time talking with Carson and was pleasantly surprised to learn how much he knows about education.

“I was most impressed with his views on education. It’s a strength. It’s a tremendous strength,” he said. So Carson is “going to be involved with us,” particularly on health and education.

In fact, Carson has some, well, interesting ideas about education and about history.

A look at his website on the issue of education shows no details about improving public education other than five “principles to restore American exceptionalism in our schools.”

Then it says: “To be successful, we must take the federal bureaucracy out of education and concentrate on empowering the American people.”  It is unclear whether Carson knows that Congress in December passed a new K-12 education law — to replace No Child Left Behind — that significantly reduces federal power over local school decisions.

The website says, “Diagnosis: The American education system is failing our children” and as “proof” it cites a “2012 study conducted by the Organization for Economic Co-operation and Development” that says “the United States was ranked 27th out of 34 countries in mathematics.”

Actually, he seems to be referring to international PISA test scores in 2012 in which U.S. students who take the exams are ranked 27th in math, 17th in reading, and 20th in science out of 34 OECD countries. The report says that there has been little to no change in the U.S. ranking over time. What that means is that U.S. students on these international tests — and, actually, on all international tests — have always ranked average or worse, even when the U.S. public education system was supposed to be the envy of the world. There are numerous problems with looking at PISA or other international test scores as valid measures of student achievement. When broken down demographically, wealthy U.S. students generally do as well as any other students in the world on these exams. That speaks to the great wealth divide in American education and society. Also, there are many public schools that are not failing children, and it is just wrong to suggest the entire system is broken.

His website then goes on to say this:

The 2015 Math and Reading National Assessment of Educational Progress scores showed a continuation of the achievement gap between white and minority students, even after the implementation of Common Core Standards in 42 states and the District of Columbia.

Whether you like the Common Core or not, most states had just begun to implement it — and many did a poor job of implementation — so suggesting they should have been able to raise NAEP scores is silly. NAEP is a national test given to groups of students across the country and is therefore sometimes called the “nation’s report card.” It is true that the achievement gap remains gaping — but  Carson’s prescriptions for fixing it don’t seem likely to help.

His website, for example, calls for school choice, such as school vouchers and charter schools. We’ve had both for a few decades and nowhere has the achievement gap been closed as a result. In fact, even on the dubious and narrow measure of standardized test scores favored by many school reformers, charter and voucher schools have not been proved to be really successful.

He has also said or written some things that raise questions about how much he really knows about the subject — or traditional academic subjects. For example:

* Carson doesn’t believe in evolution. He is a Seventh-day Adventist who believes in creationist theory that holds that all life on Earth was created by God about 6,000 years ago. It rejects Darwin’s theory of evolution, which is the central principle that animates modern biology, uniting all biological fields under one theoretical tent, and which virtually all modern scientists agree is true.

* Last year, he said, “The best education is the education that is closest to home, and I’ve found that for instance home-schoolers do the best, private schoolers next best, charter schoolers next best, and public schoolers worst.” Well, no. Though he doesn’t say on what measures he is basing this opinion, even if he is using test scores, charter schools on the whole don’t do better than traditional public schools. His statement also raises the question about whether he knows charter schools are public schools. Another legitimate question seems to be whether Carson understands that comparing these different kinds of schooling are unfair because the school populations are not the same.

* He wrote in his book “America the Beautiful: Rediscovering What Made This Nation Great” that Americans were better educated in the 1830s than they are now.  He wrote about “an example of questions in a sixth grade exit exam from the 1830s. I doubt most college graduates could even come close to passing it today.” The questions he uses aren’t actually from an 1830s test but from an 1895 test, which most students who took it flunked. (You can see more on this, plus the actual questions, here.)

* In his book, “A More Perfect Union: What We the People Can Do to Reclaim Our Constitutional Liberties,” he wrote:

“German citizens were disarmed by their government in the late 1930s and by the late 1940s Hitler’s regime had mercilessly slaughtered 6 million Jews and numerous others whom they considered inferior. Through a combination of removing guns and disseminating deceitful propaganda, the Nazis were able to carry out their evil intentions with relatively little resistance.”

Carson, during a CNN interview last year, defended the statement, expressing a view about gun control and Nazi Germany that is embraced by some gun-rights advocates — all of whom apparently didn’t learn, or forgot, what kids learn as early as middle school about the Nazi war machine. Jews were not allowed to carry guns under Nazi law, so the notion that disarmament helped increase the victim totals is nonsensical. Jews resisted as best as their circumstances allowed. Middle school kids learn this. (You can read more about this here.)

* In 2014, he denounced a new Advanced Placement U.S. history framework, which had become the target of intense criticism from conservatives. He said that “most people” who complete the course would then be “ready to sign up for ISIS.”