It Takes a Village Academy, a small high school in Brooklyn, earned an A on its latest school progress report. The four-year graduation rate was almost 86 percent, far above the citywide average. But just 12 percent of the students who entered four years earlier were considered ready for college based on their Regents test scores.

That difference of more than 70 percentage points dramatizes how large a gap there can be between the skills of a high school graduate and what is required for college-level study. Citywide, 29 percent of high school students in 2012 were considered college-ready within four years. That’s less than half of the latest citywide graduation rate, which was above 60 percent in 2011. And at some schools the gap can be far more.

Schoolbook reviewed the 10 high schools with the biggest differences between their college readiness indexes and graduation rates on the new report cards. We found gaps of more than 70 percentage points at all of them. At the FDNY High School for Fire and Life Safety, 77 percent of students graduated in four years but zero percent were considered ready for college based on their Regents scores.

School officials say these gaps show there’s still work to do, but they insist schools are making progress. In fact, all 10 schools received A’s and B’s on their new report cards.

At It Takes a Village Academy, principal Marina Vinitskaya said 40 percent of her students are English language learners who recently came to the U.S. from countries including Haiti, Yemen and Africa; and many of her students scored poorly in middle school.

“If you think about it, how many graduated with a Regents diploma, we did a very good job because these children really were struggling and they graduated in four years,” she said of her 86 percent on-time graduation rate. She founded the small school six years ago in the former Samuel Tilden High School in East Flatbush, Brooklyn.

The state requires students to score at least a 65 on five Regents exams to graduate. But the city defines college readiness as scoring at least a 75 on the English Regents and an 80 on a math Regents, based on what students need to avoid taking remedial courses at CUNY. Chief Academic Officer Shael Polakow-Suransky said many of the schools with low college readiness rates have the most challenging students.

“What we see in some of these schools is they made significant strides in going from a 50 on the Regents to 65 or 70, but not 75 or 80,” Suransky said. He added that the city’s push to measure schools according to college readiness only started a couple of years ago.

“They need to build time and we need to work with them to provide that support,” he said, pointing to programs like the Expanded Success Initiative for black and Latino males.

The 10 schools on the list are mostly small schools that replaced large, failing high schools. There is also one charter school on the list.

The city’s new college readiness index counts toward 10 percent of a school’s overall progress report score. It includes more than just Regents scores. There’s another component that measures how many students take rigorous courses that can prepare them for college. At It Takes A Village Academy, for example, the principal noted that 80 percent of her students take rigorous courses such as accounting, philosophy, and Advanced Placement classes.

The city also looks at how many of a school’s students enroll in post-secondary programs. At It Takes a Village, 88 percent of students who entered as freshmen were enrolled in college six months after graduating.

This is why educators say Regents scores, alone, aren’t always a good predictor of college readiness. “Sometimes what actually is happening belies that prediction,” said Polakow-Suransky.

The FDNY high school offers one example, he said. The school opened several years ago inside the failing Thomas Jefferson high school campus in East New York. Although 0 percent of students who entered in 2008 were ready for college based on their Regents scores, alone, the Department of Education has data showing 78 percent of those who started at the high school in 2005 and enrolled in college or vocational program after graduation persisted for at least two semesters. And 39 percent made it to their fourth semester. The school earned a B on its latest report card.

Schoolbook also looked at the 10 schools with the smallest gaps between their graduation rates and college readiness indexes. They included the city’s most selective and challenging schools. For most, there was no difference between the college readiness rate and the graduation rate (of nearly 100 percent), including Stuyvesant High School, the High School of American Studies at Lehman College, Queens High School for the Sciences at York College and Bronx High School of Science. Eleanor Roosevelt High School in Manhattan was the only one where the college readiness rate, of 93.4 percent, was a few points below the graduation rate of 97.8 percent.