As I learn more about community colleges, one of the most surprising lessons has been the sloppy and deceptive ways that students are introduced to courses. Placement tests are not well explained to students. Whether you have a passing score or not can depend on which college you attend.

At least as unsettling are studies showing that dual enrollment courses — community college courses given to high school students — often bar applicants who have less than a B average or fail a placement test, even though they need that taste of college-level work to prepare for the real thing.

Now a troubling new research paper says that the remedial courses given to community college students who do not score high enough on placement tests often do no good. Colleges still swear by the courses, however. Students are further deceived by upbeat guidance to a community college placement test owned by the College Board that tells students, wrongly, that they can’t really fail a placement test.

In “Assessing Developmental Assessment in Community Colleges” by Katherine L. Hughes and Judith Scott-Clayton, problems with remedial courses — a harsh term now more softly rendered as “developmental courses” — are exposed in ways I rarely see in community college brochures.

“More than half of entering students at community colleges are placed into developmental education in at least one subject, based primarily on scores from these assessments, yet recent research fails to find evidence that placement into remediation improves student outcomes,” the authors conclude. “While this has spurred debate about the content and delivery of remedial coursework, another possibility is that the assessment process itself may be broken.”

My parents both graduated from community colleges. My brother spent much of his career working at one. These two-year colleges, from which students can transfer to four-year schools, are vital to our education system. Nearly half of all college undergraduates in the country are enrolled in community colleges.

But they get little attention from reporters like me, even as they become increasingly important. Without community colleges, the growing efforts of high schools to prepare even disadvantaged students for college are not going to get very far.

It doesn’t help when an institution as important to that effort as the College Board gives confusing advice to students taking the ACCUPLACER placement test it sells to community colleges. Hughes and Scott-Clayton quote a College Board guide saying: “You cannot ‘pass’ or ‘fail’ the placement tests, but it is very important that you do your very best on these tests so that you will have an accurate measure of your academic skills.”

The report authors say: “While it is true that students receive numeric scores rather than passing or failing grades, 92 percent of two-year institutions use the resulting scores for placement into remedial education. ... Often, placement is determined solely on the basis of whether a score is above or below a certain cutoff. Thus, despite the College Board’s reassuring language, placement exam scores are commonly used not merely as a measure of skills but rather as a high-stakes determinant of students’ access to college-level courses.”

Spokeswoman Sandra Riley gave me a statement from the College Board in response to the report by Hughes and Scott-Clayton. It said the guidance to students taking the ACCUPLACER test was phrased that way because “we believe that students who will require remediation but have the desire to obtain a college degree deserve encouragement. To inform students that they are failures as they are seeking to redefine themselves or get insight into their own college potential would be counterproductive.”

You often can’t take a course in a community college that will earn credit toward your degree if you score below the minimum on a placement test. You must then take a remedial course — which you must pay for — even though the time and effort you devote to it does not count toward your degree.

The report authors say estimates of the annual cost of providing remedial instruction range from $1 billion to $4 billion. “Students additionally face the opportunity costs of the extra time that remediation requires, potentially delaying their progress toward a credential,” they say.

Looking at several pieces of research, the authors conclude that the placement tests predict fairly well how students will do in their first college course. The College Board said its ACCUPLACER test led to successful placement of 70 percent of students, based on several studies, when “success is defined as a grade of B or higher or C or higher.” Hughes told me she thought the College Board was very dedicated to improving the process of how assessments are used for placements.

The paper describes efforts to improve the placement system and cut down on the waste of time and money. The placement tests and their cutoff scores are gradually becoming more standardized, the authors say. The movement to create state-wide and national standards in K-12 tests is pushing the community college systems in the same direction. The authors say this may handicap administrators who want better ways of measuring who is ready for credit courses.

One California study, the authors say, suggests that placement improves when higher scores are given to students whose high school records are stronger. Multiple indicators of college readiness being explored include “non-cognitive” measures such as a positive attitude, a focus on long-term goals, availability of a strong support person, leadership experience, community involvement and knowledge acquired on a job.

One approach that makes sense to me, and has yielded promising results in California, is to give the community college placement tests to students in their junior year of high school, the study says. It helps them become familiar with the tests and allows them to take high school courses — for free — that will prepare them to do better on the placement tests when they are ready to enroll in college. The College Board statement said it supports use of multiple measures.

Community colleges have been hit hard by state budget cuts. Their professors still struggle to communicate with students who do not fit the usual collegiate mold. But making the placement system clearer and making it better at assessing readiness would help fulfill the promise that in these colleges, at least, you can get an education in your home town without going broke.