A “Jobs” banner hangs outside the U.S. Chamber of Commerce in Washington, D.C., in this file photo from 2014. (Photo by Andrew Harrer/Bloomberg)

College freshmen now regularly say the No. 1 reason to attend college is to “get a better job,” according to a major annual survey of incoming students conducted by UCLA. Before 2006, students told researchers that the top reason to go to college was to “learn about things that interest me.”

That college is seen as a training ground for a job is perceived by professors as anathema to their mission of broadly educating students. Most will tell you that their job is not to get their students a job after graduation. As a result, that responsibility is usually left to career centers, which typically are underfunded and often tucked away in a corner of campus that students don’t find until their senior year, if ever.

And for the most part, career centers are failing students, according to new research out this week from Gallup and Purdue University.

In a survey of more than 11,000 college graduates, the Gallup-Purdue Index found that fewer than half of recent graduates — those who graduated since 2010 — found the career center helpful or very helpful. And that’s just among the students who visited the career center at least once. Six in 10 recent graduates said they never visited the career office as an undergraduate.

Among the graduates of all years who said in the survey that career services were very helpful, 49 percent of them said that they had a good job waiting for them after graduation. Just 15 percent who said career services weren’t helpful said the same about their job prospects after graduation.

No wonder so many students are struggling to launch after college. Nearly half of new graduates are underemployed, working jobs that don’t require a bachelor’s degree, according to the Federal Reserve Bank of New York. A study that was released last week found that the likelihood young adults will earn more than their parents has fallen dramatically in the past few decades. Just half of Americans born in 1984 earned more at age 30 than their parents did at the same age.

College officials will defend their career services by saying students share the responsibility in finding a good job after graduation, and they are certainly right in that assessment. Students find jobs in all kinds of ways, not just by visiting the career center. The Gallup survey found that 20 percent of students acquired an internship or job through a friend. Another half found their jobs through professors or other staff members on campus.

Such informal networks, often established for the first time in college, are the way many students find out about internships and jobs. It’s the reason students, and especially their parents, drive themselves crazy to get into Stanford or Harvard. It’s not because the education is so much better at those places; it’s because of the network students connect to, through the parents of their classmates, alumni, and eventually through the students themselves when they become alumni.

Navigating that network, however, is difficult for many students. Fewer than half of college seniors in the annual National Survey of Student Engagement, a poll of college freshmen and seniors, said they talked often with a faculty member about their career plans.

At selective colleges, students who lack social capital, particularly lower-income students, often find it tough to plug into a network. Affluent students typically can draw on family resources after college to make up for their weak academic records as undergraduates, according to a study of freshmen women at Indiana University that resulted in the 2013 book, Paying for the Party.

So while a group of elite colleges pledged this week to enroll 50,000 more low-income students in the coming decade, they will need to do more than just provide them the aid for tuition and living expenses. Those students will need help in navigating the informal campus networks, and in getting the internships during college that are of increasing importance for landing a good job afterward.

One way that colleges can better support low-income students in finding meaningful work is through the federal work-study program. The federal government picks up 75 percent of the cost of students in the program (with the colleges picking up the other 25 percent). But most of those jobs are on campus, and typically low-skill jobs, such as in the dining hall or as office assistants or working the desk at the recreation center — positions that usually don’t provide students with many marketable skills.

While there are some limitations, colleges can partner with off-campus employers and use work study funds to place students in jobs that will help their résumés. But colleges with tight budgets prefer to fill on-campus jobs with work-study students, and many financial-aid officials say they don’t have the time or the expertise to establish partnerships with off-campus employers.

The economy and the job market have evolved in ways that make the typical college playbook for preparing students for post-graduation no longer relevant. Graduates expect colleges to help them find jobs. Those in the Gallup-Purdue survey who said their career offices were helpful were three times more likely than those who didn’t to think their degrees were worth the price and two and half times more likely to donate to their schools.

Perhaps it’s that last finding that will finally persuade colleges — and even professors — that it’s part of their job to help students find jobs.