At the end of “The Special-Education Charade,” a recent article in The Atlantic about why having a “special” child in public schools is “hell, or its equivalent,” readers confront a pertinent phrase: “the dismal state of teacher training.”

This was only one of several factors noted in Tracy Thompson’s emotional — and spot-on, as I can attest as a former special education teacher — 2,000-plus-word tirade about how educating special-needs kids in mainstream classrooms has become a labyrinth of pain and nonsense. But it’s a factor worth illuminating.

Not least because the special education trend in schools is increasingly to move away from separate special ed classrooms, catering to specific needs such as learning disabilities or emotional/behavioral disorders, in favor of putting students with sometimes-profound disabilities in general classes.

This is called putting a student in the “least restrictive environment” so he or she can learn in the company of students who are roughly the same age, regardless of whether they have the same capacity for being able to perform the tasks expected of them, with or without assistance.

This placement results in anything from an eighth-grader who reads at a first-grade level getting placed in a mainstream history course to a high school senior who can’t readily compute simple mathematical problems but is placed in a regular biology class. Sometimes, but not always, such students are provided with a “one-on-one” assistant to facilitate their learning.

More often these students simply show up in the classrooms of regular teachers who have no specialized training in the instruction of children with cognitive, behavioral or emotional disabilities. The teachers are likely, but not always, privy to the student’s background and will have, at most, a few excerpts from a very long legal document called an “Individualized Education Program” (IEP) that explains what accommodations the teacher is required to provide the student.

These assistive methods usually fall within the realm of things like “preferred seating,” “permission to leave class as needed,” notes provided to the student ahead of class, the opportunity for longer times to take quizzes and tests or having them read aloud.

Many of these teachers in middle school and high schools have more than 100 students spread across multiple classrooms per day. In some cases, six or seven students with IEPs wind up in a single class period.

Setting aside whether this is good policy — that is, whether both the special needs children and non-special needs students in a given classroom get the most benefit out of their educational experience — you have to consider the extra burden on teachers who are already not as well equipped for such high-stakes teaching as one would hope.

According to the National Council on Teacher Quality’s 2015 State Teacher Policy Yearbook, a scant 26 states require all middle-school teachers to pass a test in every core subject they will teach. And just five states — Indiana, Minnesota, Missouri, South Dakota and Tennessee — require secondary school teachers to demonstrate their knowledge of the subjects they’ll teach.

And it’s not as though teachers who do have special education expertise are so rigorously prepared, either.

According to the council, “With just a few exceptions, state licensing policies for special education teachers are abysmal. Twenty-one states still allow special education teachers to earn a generic special education license to teach any special education students in any grade, K-12. ... Only 14 states require elementary special education candidates to demonstrate content knowledge on a subject-matter test -- similar to what would be expected of any other elementary school teacher. Only Missouri, New York and Wisconsin require secondary-level special education teachers to pass a test in every subject they are licensed to teach.”

There are no quick and easy fixes for the many factors that lead public schools to perform poorly in educating our children — regardless of whether individual students need special help. But the low standards for training teachers who are in charge of our nation’s classrooms should be a no-brainer way to start remedying at least part of the problem.

Teacher training isdismal and, unfortunately, not a headline-grabbing education issue that motivates parents and other advocates to demand change.

But shouldn’t it be?

Esther Cepeda’s email address is estherjcepeda@washpost.com. Follow her on Twitter, @estherjcepeda.