The number of students in virtual schools run by educational management organizations rose sharply last year, according to a new report being published Friday, and far fewer of them are proving proficient on standardized tests compared with their peers in other privately managed charter schools and in traditional public schools.

About 116,000 students were educated in 93 virtual schools — those where instruction is entirely or mainly provided over the Internet — run by private management companies in the 2010-11 school year, up 43 percent from the previous year, according to the report being published by the National Education Policy Center, a research center at the University of Colorado. About 27 percent of these schools achieved “adequate yearly progress,” the key federal standard set forth under the No Child Left Behind act to measure academic progress. By comparison, nearly 52 percent of all privately managed brick-and-mortar schools reached that goal, a figure comparable to all public schools nationally.

“There’s a pretty large gap between virtual and brick-and-mortar,” said Gary Miron, a professor of evaluation, measurement and research at Western Michigan University and a co-author of the study.

“E.M.O.’s” — educational management organizations, a term coined by Wall Street in the 1990s — now operate 35 percent of all charter schools, enrolling 42 percent of all charter school students, according to the report. “Charter schools are publicly funded and they are serving public school students,” Dr. Miron noted. “But they are increasingly privately owned and privately governed.”