In comfy suburbs from the East Coast to the Midwest and from the Rockies to the Southwest, large proportions of middle-class students are failing to perform well in their core academic subjects.

That's the disturbing conclusion of a massive two-year, five-state series of studies by the Pacific Research Institute. The studies looked at regular public schools in Illinois, Texas, Michigan, Colorado, and New Jersey where students were predominantly "non-low-income" -- that is, where less than one-third of the school population qualified for the federal free and reduced lunch program.

The studies looked at various student-performance indicators, including results on national and state tests, plus the SAT.

On the National Assessment of Educational Progress exam, around half of non-low-income eighth graders in New Jersey, Illinois, and Colorado failed to score at the proficient level in reading.

Worse, in Texas and Michigan, more than half of non-low-income eighth graders failed to achieve proficiency in reading.

The state tests examined in the PRI studies varied in content difficulty and scoring rigor. In Texas, for example, the state currently sets a low scoring benchmark for "proficiency" on state tests. But that benchmark will be raised to a more rigorous and telling level in a few years.

If that more rigorous proficiency scoring benchmark is used, then 60 percent of Texas public schools with predominantly non-low-income student populations had half or more of their students in at least one grade level failing to achieve proficiency on state math or reading exams in 2013.

An especially troubling note for an American economy increasingly dependent on worker knowledge of science, technology, engineering, and math is the poor performance among middle-class students on math exams.

In Michigan, nearly half of predominantly middle-class public schools had 50 percent or more of their students in at least one grade level failing to achieve proficiency on a 2013 state exam. Most of that failure was in mathematics.

In Colorado, 75 percent of predominantly middle-class public high schools had half or more of their students failing to achieve at the proficient level on a 2014 state exam -- mostly on the math test.

The failure of middle-class students to perform proficiently on K-12 national and state exams has consequences for exams linked to higher education.

In New Jersey, nearly three out of 10 predominantly middle-class public high schools had 50 percent or more of their students failing to reach the college-readiness benchmark score on the SAT. It's no wonder then that many students in New Jersey, as in other states, must take remedial-instruction courses once they get to college.

To get a real flavor for the problem of underperforming middle-class schools, look at some individual schools.

Castle View High School is in Castle Rock, Colorado, which has been named by various publications as one of America's best places to live. Although only about one in 10 students were socio-economically disadvantaged, 58 percent of the school's tenth graders failed to score proficiently on the 2014 state math exam.

Grosse Point North High School is in tony Grosse Pointe Woods outside Detroit. On the 2013 state math test, 59 percent of the school's eleventh graders failed to hit proficiency. No wonder that one alumnus of the school, who went on to attend the University of Michigan, posted, "I felt unprepared my first year of college."

At Waldwick High School in affluent Bergen County, New Jersey, only a microscopic one percent of the school's students were socio-economically disadvantaged. Yet 56 percent of students taking the SAT failed to score at the college-ready level.

For middle-class parents, such results should be a wake-up call. School-quality problems are not just limited to poor inner cities. Every child -- rich, poor, and middle-class like -- should have the right to a good education. If the neighborhood public school isn't providing it, the child should be able to go somewhere else.

Lance Izumi is Koret senior fellow and senior director of education studies at the Pacific Research Institute. He is the author of PRI's five-state series of "Not as Good as You Think" studies.