Hit the books — and the bank.

The No. 1 piece of advice recent college grads would give their 18-year-old selves is to work to earn some money while they’re in college, according to data that will be released Thursday by financial services firm TD Ameritrade. Indeed, 17% said this was the one piece of advice they’d give their younger selves, making it the top answer.

Part of this, of course, is that many students took on a staggering amount of debt while going to school, and now may wish they had offset some of that with a job. The average class of 2016 graduate has $37,172 in student loan debt, up 6% from last year, according to data from Student Loan Hero. And the average monthly student loan payment for borrowers aged 20 to 30 years is $351 — a lot for the thousands of low-paid and underemployed grads.

But many recent grads who worked for pay while in school say it’s about more than just extra money. For Steph Taylor, 24, who graduated from Queensland University of Technology in 2014, it helped launch her career. “I secured an accounting job that I worked at while I was studying and it definitely played a huge part in getting my so-called ‘dream job’ once I graduated,” she says (Stephanie took a full-time accounting position upon graduation). “It also makes the transition from being a student to being full-time employed a lot easier, as you already have the work ethic and you have a slightly more realistic expectation of what the workplace will be like.”

Jonathan Goodwin, 24, worked several paying jobs while in school at Purdue University, including one doing IT customer service for his university. In addition to earning some extra money to pay his rent and fund a “few pub crawls along the way,” he says this job “taught me how to manage schedules and stress and how to troubleshoot, as well as interacting with virtually every kind of person.” These are skills he still uses today in his job as a marketing coordinator for Applico, he says.

Of course, some of these skills could also be learned in unpaid internships, but for many students those aren’t an option because they need the money. And earning money while in school teaches you money skills you’ll need in the real world, as freelance media and political consultant Brian Harrington, 25, learned from doing a part-time marketing job while in school at Azusa Pacific University. “It taught me how to save and invest my money,” he says. “Often times when you’re self-employed you’ll go through high times and low times so the cash flow management I practiced through that job helps me on a monthly basis now.”

Other popular answers to the question of top advice to your 18-year-old self include “work as hard as you can in college, enjoy yourself later” (14%) and “pick the right program of study to secure employment (13%). Both speak to the struggles recent college grads have had in securing well-paid, full-time employment.