The various reports calling for more rigorous high school preparation tend to be based on a few underlying assumptions, one of them being a strong positive correlation between completing a core college preparatory curriculum and college/workplace success.

But Rigor at Risk: Reaffirming Quality in the High School Core Curriculum, a new report released Tuesday by ACT, the nonprofit testing entity, shatters the assumption that simply completing a recommended core college preparatory curriculum – with at least four years of English, and three of math, science and social studies -- sufficiently prepares students for success.

Among the more than 647,000 ACT-tested 2006 high school graduates who took the core curriculum, only about one in four (26 percent) met all four of the ACT College Readiness Benchmarks in English, math, reading and science (meeting or surpassing the benchmarks signifies a high likelihood that students will earn a “C” or higher in first-year college courses like composition, algebra and biology). About one in five of those students who took the core curriculum, or 19 percent, failed to reach any of the benchmarks.

It's important to note, though, that while the core courses might not be adequate in themselves, students who pursue a core college preparatory curriculum do better than their peers who don't: Just 14 percent of ACT-tested 2006 graduates who did not take the core curriculum met all four benchmarks, with 36 percent meeting none.

Still, the sobering statistics go on, reflecting concerns about grade inflation, watered-down content, and mixed, even misleading messages potentially being sent to high school students: Nearly half of ACT-tested 2005 graduates who earned an "A" or a "B" in an algebra II class were not ready for a first-year college math course; in physics, the proportion achieving "A's" and "B's" unprepared for college science was higher than half. Only when students take 4.5 years of English and math do about 75 percent of them reach the college readiness benchmarks, and in science and social studies, only 38 and 55 percent of students reach the college readiness benchmarks after four years of instruction.

With three years of math, social studies and science instruction -- the number required under the core curriculum -- just 16, 50 and 26 percent of 2006 high school graduates met the college readiness benchmarks in the three respective disciplines. With four years of English (again, the amount required in the core curriculum), 67 percent met benchmarks.

“Our latest research shatters a promise that we’ve made to our children” – that if they take the core curriculum, they will graduate prepared for work and college, Cynthia B. Schmeiser, president and chief operating officer of ACT’s education division, said during a Tuesday press event in Washington.

“Students today,” said Schmeiser, “do not have a reasonable chance of becoming ready for college unless they take additional courses beyond the core.”

ACT researchers argue that rather than overload students with extra courses in order to prepare them for college, high schools need to improve the quality and rigor of their core course offerings. Schmeiser cited, for instance, ACT’s identification of nearly 400 high schools that have shown greater-than-average increases in ACT math and science test scores – and the finding that the increases are associated with substantial numbers of students taking rigorous courses in algebra II and chemistry.

Recommendations in the report include aligning high school course outcomes with college readiness standards, hiring qualified teachers and providing professional development support, expanding access to high-quality core courses, measuring results incrementally at the course level and specifying the number and kinds of courses that students need to take to graduate from high school ready for college and work. The report finds that more than half of the states do not require students to take specific courses in math or science in order to graduate from high school, only 12 states require algebra II, only 17 explicitly require biology, two require physics and just one state requires chemistry. ACT recommends four years of English, three years of math including algebra I, algebra II and geometry, three years of social studies and three years of science, including biology, chemistry and physics.

Yet, not only can the number of courses taken be misleading, so too can the content, pointed out Chrys Dougherty, director of research at the National Center of Educational Accountability. For instance, when students enter algebra I unprepared, the teacher may adjust the instruction to a lower level accordingly. All the sudden it’s not Algebra I even more -- although a student’s transcript might record an "A" in the subject. “What they essentially have,” Dougherty said Tuesday, “is orange drink in cartons labeled orange juice.”

In a time of high enrollments in remedial courses and concern about college graduation rates, the net effect of pursuing a curriculum presumed to be college preparatory -- and being rewarded as presumably college-ready with high grades -- could be quite costly when those high school students hit the college classroom only to find, sometimes to their surprise, that they're unprepared. With the doubling of tuition and tripling of loan debts in recent years, the cost of failing, stressed Stanley G. Jones, commissioner for the Indiana Commission for Higher Education, has never been higher.

“For too many people, college is a false promise,” said Jones, “if students aren’t prepared for a college education.”