Very few people look back on their college years and say, "I wish I drank more beer" or "I should have eaten more pizzas." Many of us, however, do look back and regret the classes not taken, the internships passed up, and the other opportunities we squandered.

Our panel of Motley Fool contributors have all gone on to successful and interesting careers. That does not mean, however, that they have no regrets. There are mistakes we all made in college that we wish we could have back.

Srudents throw their caps in the air wearing graduation robes

Many people have regrets about their college years. Image source: Getty Images.

I wish I'd joined in more activities  

Selena Maranjian: I loved my college years and still have some good friends from those now long-gone days. But I could have had more good friends from college, and I sometimes wish I did. I have always been on the shy side, so I didn't participate in nearly as many activities as I could have -- and in each of those activities, I would likely have made more friends. Instead, I made friends among those who lived in the same dorms, took the same courses, or worked alongside me in the cafeteria.  

That's all good, but had I been more active in college -- perhaps writing for the school newspaper or being part of the movie society or even trying some intramural sports, I'd have met even more interesting people.  

It's always good to have friends, just because friends are wonderful. They can also come in handy, career-wise: They may be able to offer insights into the industries and companies they work in, and on occasion, they may be able to help you land a great job.  

Venturing out of one's comfort zone can be hard, but it's often very rewarding and worthwhile.

Taking an unpaid internship that would've helped my career

Maurie Backman: Like many students, I financed much of my college education by working during my studies and taking out loans. So when a good job opportunity arose my senior year, I jumped on it because of the pay. There was just one problem: that job conflicted with an internship I'd been looking into at a local publication, so taking it meant giving up the opportunity to get some journalism experience that could've helped my career.

Had the internship paid anything, I would've chosen it in a heartbeat, especially since the other job had nothing to do with the career path I was looking at. But at the time, I felt I needed the money and couldn't afford to work for free when I was racking up thousands in tuition bills.

All in all, I think I managed to make the most of college. I had several majors, gained work experience, and made some connections that helped me after graduation. But I do sometimes regret passing up that internship, because it possibly could've opened other doors for me sooner.

I wish I had been a bit more of a student

Daniel B. Kline: I was not very good at the academic part of being a student. Even though I had amazing professors -- more than one whose name you might recognize -- I had very little interest in the classroom side of things.

Instead, I threw myself into campus activities. I wasn't goofing off or going to parties -- I was generally doing useful things. I spent a semester as editor of the campus humor magazine, nearly two years as co-editor of the school's weekly newspaper, and hosted television and radio shows on campus. I also served on the school's food service committee because of a column I wrote about a lack of labels making it impossible to distinguish between vanilla (delicious) and banana (horrendous) pudding.

Add in the fact that during my senior year, while still editing the school newspaper, my part-time job turned into a career-starting full-time job. That was all great and it contributed to who I am today but had I done fewer nonacademic things -- just a few -- I may have actually experienced more.

My freshman year advisor, for example, went on to become a noted historian who writes books, appears on news programs, and is a sort of minor celebrity. I probably skipped a third of his classes (good by my attendance standards) because I was doing something else on campus.

Being active on campus is important, but it was too much of my college experience. If I'd focused a little more on soaking up what my impressive collection of teachers had to offer, I might have learned a lot more.

The Motley Fool has a disclosure policy.