Jon Boeckenstedt, a DePaul University official, tries a virtual campus tour device from YouVisit. Admissions counselors and recruiters looked at new technology during an annual admissions convention in Indianapolis. (ALAN PETERSIME/For The Washington Post)

Every year, high school students stress over whether they’ll get into their top-choice college. But this week, college admission officers from across the country are gathered here to contemplate their own big worries.

Will students choose them? Will students even find them?

The 70th annual convention of the National Association for College Admission Counseling brought together 6,000 professional matchmakers from colleges, high schools and private companies in the field. Many of them are grappling with a technological revolution in how students search for colleges, an upheaval with huge implications for recruiting.

Consider DePaul University in Chicago, the nation’s largest Catholic University, with about 24,000 students. Jon Boecken­stedt, 55, associate vice president for enrollment management and marketing, is paid to keep students coming in the door.

Every cycle starts with a list of perhaps 300,000 to 350,000 names and addresses of students who might be interested in what DePaul offers: a diverse research university in the heart of a big city. Boeckenstedt buys these leads from the ACT and College Board testing organizations as well as a company called Cappex, which helps students manage their college search.

DePaul sends these prospects information and waits for replies. “It’s like me saying, ‘Do you want to go on a date?’ ” Boeckenstedt said Friday. Perhaps 50,000 to 60,000 express interest through the mass-mail outreach or other avenues. These, he said, equate to “Maybes.”

About 20,000 end up applying. “A date,” Boeckenstedt said.

About 12,500 get offers. “Proposals.”

About 2,500 accept. “Marriage.”

With variations, this scenario unfolds annually for selective colleges and universities. But schools face peril at every step of the way in a fluid and highly competitive market. Their “maybes” might fall short — a concern. Their “dates” might fall short — a bigger worry. If their “marriage” count — enrollment — falls short, then colleges face major trouble because tuition revenue pays most of their bills.

“You need cash to run the business,” Boeckenstedt said. “That’s always, always been true. That’s never not been true.”

So every year, Boeckenstedt and his peers are looking for new tools to ensure a steady flow of recruits. Enter entrepreneurs such as Abi Mandelbaum.

The chief executive of YouVisit, a Web platform for virtual tours, Mandelbaum was one of scores of vendors in an exhibit hall at the Indiana Convention Center. He told Boeckenstedt that he could put together an interactive video package to help DePaul show off its campus via the Web for a price starting at $3,000.

Mandelbaum said his site offers virtual tours of about 1,000 colleges, including big names such as Dartmouth College and Yale University. The idea is to enable students to scope out a campus in detail without having to drive or fly there. That helps them narrow a search.

Plenty of other tech-driven ventures were on display. There was Chegg, which owns the Web site Zinch.com, a competitor of Cappex. Both companies sell names of students who are interested in specific schools, a potentially valuable pool of leads.

There was Niche, which owns a Web site of the same name that used to be called College Prowler. “We survey students at all the colleges,” said Mark Tressler, vice president for business development. “They tell us what it’s like — housing, academics, the meal plans. Basically, we’re a Yelp for major life decisions.”

There was PrepTalk, which helps recruiters connect with students through webcasting, in one-on-one sessions or one-to-1,000. Katie McDonald, chief operating officer, said some students will stay with the webcasts for 45 minutes at a time. “Which for a 17- or 18-year-old is not bad,” she said.

And there was CollegeWeekLive, which hosts live chats with prospective students and admission officers. The premise behind these and other ventures is to use the means of communication that prospective students favor — smartphones and tablet computers — to influence what might be one of their most important decisions in life.

That is a difficult technological leap for many colleges that are accustomed to recruiting the old way, through relationships with high schools, reliance on brand names and mass mailing to prospective students.

“We’re in massive flux in terms of what’s going on in higher education,” said Robert Rosenbloom, president and chief executive of CollegeWeekLive. Many schools, he said, “don’t have the necessary marketing skills and technological skills to really meet the students where they are.”

Boeckenstedt, a 32-year veteran of college admissions, is somewhat unusual among his peers. He relishes demographic data, disdains the popular obsession with ultra-selective colleges and tries to keep pace with technological changes. He said he counts himself among the fortunate in his field, because he has never felt pressure from his superiors to raise DePaul’s applicant total for the sake of appearing to be more selective.

“Not once in 12 years has anyone ever asked me that,” he said.