Is it my imagination, or have you noticed that some public high school courses that are now called "honors" are equivalent to the regular "college prep" curriculum of earlier eras? And have you also noticed that what is now called "college prep" is aimed largely at students who are deemed low achievers or of low cognitive ability?

In fact, this trend is nobody's imagination. Over the past generation, public schools have done away with "tracking" -- a practice that began in the early 1900′s. By the 20′s and 30′s, curricula in high schools had evolved into four different types: college-preparatory, vocational (e.g., plumbing, metal work, electrical, auto), trade-oriented (e.g., accounting, secretarial), and general. Students were tracked into the various curricula based largely on IQ but sometimes other factors such as race and skin color. Children of immigrants, and children who came from farms rather than cities, were often assumed to be inferior in cognitive ability and treated accordingly.

During the 60's and 70's, radical education critics such as Jonathan Kozol brought accusations against a system they found racist and sadistic. They argued that public schools were hostile to children and lacked innovation in pedagogy. Their goal -- which became the goal of the larger education establishment -- was to restore equity to students, erasing the lines that divided them by social class and race. The desire to eliminate inequity translated to the goal of preparing every student for college. The goal was laudable, but as college prep merged with the general education track, it became student-centered and needs-based, with lower standards and less homework assigned.

Some of the previous standards returned during the early 80's, when the "Back to Basics" movement reacted against the fads of the late 60's and the 70's by reinstituting traditional curricula. But the underlying ideas of Kozol and others did not go away, and the progressive watchword in education has continued to be "equality."

As a result, grouping students according to ability -- a practice viewed by many in the education establishment as synonymous with tracking -- has been almost completely eliminated in K-8. Instead, most schools practice full inclusion, which means educators are expected to teach students with diverse backgrounds and abilities in the same classroom using a technique known as "differentiated instruction."
Unfortunately, the efforts and philosophies of otherwise well-meaning individuals have attempted to eliminate the achievement gap by eliminating achievement. Exercises in grammar have declined to the point that they are virtually extinct. Book reports are often assigned in the form of a book jacket or poster instead of a written analysis. Essays now are "student-centered" -- even history assignments often call upon students to describe how they feel about past events rather than apply factual analysis. Math classes are now more about math appreciation and being able to explain how a procedure works rather than the mastery of skills and procedures necessary to solve problems.
An exception can be found in gifted and talented programs. These programs -- some of which begin as early as third grade -- are a reaction against the low expectations brought on by full inclusion. These programs often make matters worse. They can be rigid, excluding late bloomers by testing them into a "non-honors" track early in life. In other words, the elimination of ability grouping has become a tracking system in itself that leaves many students behind.
Interestingly, new reports suggest that ability grouping may be making a comeback. The National Bureau of Economic Research has released a study that examines the effects of sorting students by ability. The study looked at data from the Dallas Independent School District and found that sorting by previous performance "significantly improves students' math and reading scores" and that the "net effect of sorting is beneficial for both high and low performing students." The same benefits were found among gifted and talented students, special education students, and those with limited English proficiency.

The 2013 Brown Center Report on American Education contains a study by Tom Loveless of the Brookings Institution that also looks at ability grouping and tracking in schools. The study found a recent increase in both practices -- a trend Loveless finds noteworthy, given the long-term resistance to each. He suggests a few possible reasons for the reversal: The emphasis on accountability, started by No Child Left Behind, may have motivated teachers to group struggling students together. The rise of computer-aided learning might make it easier for them to instruct students who learn at different rates. And a 2008 MetLife Survey of the American Teacher reports that many teachers simply find mixed-ability classes difficult to teach.
If ability grouping is indeed making a comeback, education may benefit significantly. Instead of relying on "gifted" and "honors" programs -- which are, in effect, tracking systems -- the ability grouping now being practiced in some schools allows for greater flexibility. When properly executed (as it was in my school during the 1960s), this enables students placed in lower-ability classes to advance to higher-ability classes based on their performance and progress.
Ability grouping by itself, however, will not be enough. Schools also need better K-8 curricula and more academic extracurricular opportunities at all levels. Most importantly, they need to hold students to specific expectations rather than leaving achievement up to some vague "natural process," like the student-centered assignments that essentially protect children from learning. 
If implemented correctly, the new ability grouping will allow the curriculum to be better tailored to meet the needs of students at all levels. Such classes would help students get up to speed more effectively. This would not only make tutors much less necessary but would also have the advantage of making advancement easier for students whose parents cannot afford tutors or learning centers. Otherwise, it will be nobody's imagination if students continue to fulfill the low expectations that have been set for them.

Barry Garelick is a writer, and middle- and high-school math teacher, based in California. He has written for The AtlanticEducation Next,Educational Leadership, and Education News and is the author ofConfessions of a 21st Century Math Teacher.