Percentages of high school graduates on Long Island and statewide who actually enrolled in college in recent years ran substantially below the number who told their districts they intended to do so, according to figures the state Education Department released Monday.
Local school officials immediately challenged the new college attendance rates, saying they exclude significant numbers of students in some instances.
The report found that 81.3 percent of public school graduates in the Class of 2012 in Nassau and Suffolk counties enrolled on college campuses in the year after leaving high school. That contrasted with the 89.4 percent of the region's graduating seniors who told their schools that same year that they intended to matriculate at two-year and four-year institutions.
The new report -- titled "Where are They Now?" -- was based on data collected by the National Student Clearinghouse, a nonprofit agency that has contracted with New York State since 2010 to track students to determine how many attended colleges and universities and ultimately graduated.
The $150,000-a-year contract has been paid through federal Race to the Top funding, state officials said. The clearinghouse, set up in 1993 and based in Herndon, Virginia, says it provides reporting and verification services to more than 3,600 colleges and universities nationwide.
Comparisons of the postsecondary enrollment in the new report and earlier state figures are not exact because of slight differences in the way the department presented the new data.
Education officials acknowledged that the clearinghouse figures were not precise in all instances, but emphasized the data's versatility. High school guidance counselors, for example, can use it to determine how many graduates experienced "summer melt" -- a term used to describe students who change their minds and decide to skip college, or who get derailed from enrollment by financial circumstances or other hurdles.
"We know there is a gap between what they [high school graduates] say in the spring and what they do in the fall," Education Commissioner John B. King Jr. said. "Just a couple hours of summer counseling can make a big difference in whether students enroll."
A recent Harvard University study, based largely on clearinghouse data, found that as many as one in five high school graduates who had been accepted by a college and intended to enroll did not do so. Reasons ranged from lack of adequate college financial aid to an inability to complete class or housing registration forms via the Internet.
Several Long Island school leaders pointed to what they described as flaws in the data, saying this could cause parents to conclude mistakenly that their teenage children were not being properly prepared for college.
"It's not accurate, plain and simple," said William Johnson, superintendent of Rockville Centre schools and a former president of the New York State Council of School Superintendents.
Johnson added that his staff had checked on 53 local graduates from the Class of 2012 who did not show up on the clearinghouse's list of students enrolled in college. Of 42 graduates contacted, 30 said they had attended college for at least a year, Johnson said.
Fred Cohen, a Nassau BOCES consultant on student data, ticked off several reasons why such students may not show up on clearinghouse rolls. For example, he said, the rolls exclude students from the United States attending universities in other countries and those enrolled in federal military academies.
Also excluded are students who ask that they not be tracked for reasons of personal privacy, Cohen added.
Clearinghouse officials did not respond Monday to a phone call and email message.
Some local school officials agreed with state authorities that the clearinghouse data could be useful in some ways -- for example, in determining whether students and their parents are getting a realistic picture of college costs. Those local officials voiced concern, however, that families could get the mistaken impression that students are not being prepared academically.
"This is wonderful information," said Susan Schnebel, superintendent of Islip schools and president-elect of the Suffolk County School Superintendents Association. "But this is not an indication of whether students are prepared."