College is generally seen as a joyful rite of passage — a bridge between adolescence and adulthood that opens all sorts of doors to young people. The educational decisions that young people make influence the options they will face over the rest of their lives. And young people, being young, often make terrible decisions. Consider what follows to be friendly advice from two college professors who have seen it all before.

The first thing you need to know is that college is expensive. You’ve heard that before, but we don’t think you understand the words. Counting the income you won’t earn while spending four years as a full-time student, your college education will cost almost a quarter of a million dollars. State schools will cost less, private and prestigious schools will cost more, but this is the average. To put that in perspective, that’s in the ballpark of the price of the median new home in the United States.

We know that you’ve been told that college is a good investment. Who tells you this? Colleges themselves — though the average $35,000 per year per student they charge in tuition and fees may cloud their opinions. Importantly, colleges get their money years before the student learns whether the degree was worth its price. What colleges don’t tell you is that a college degree isn’t necessarily valuable. But any number of college majors are.

For all that you hear about graduates who can’t afford their student loan payments, there are some graduates you never really see complaining. Among these is virtually everyone who graduated with a major in the STEM disciplines (science, technology, engineering and mathematics). These graduates do quite well for themselves. According to data from Payscale.com, average engineering, mathematics, statistics and economics majors can expect to earn $2 million to $5 million more than the average high school graduate over the course of a career.

At the other end of the scale are majors ending in the word “studies,” and majors that involve child education or family services. A child and family studies major, for example, barely recoups the cost of the degree over the course of an entire working career. The average early childhood education major with a four-year degree can expect to earn 20 percent less over a career than the average auto mechanic. The average social work major will earn 25 percent less than the average electrician. And this ignores the quarter of a million dollar cost of those degrees.

For those who choose to go to college, our advice is to delay choosing a major. Deciding the trajectory of one’s entire life at age 18 is simply not sensible. And while deciding at age 20 might not be the best idea either, it is a significantly better idea. Students at the end of their sophomore year have a lot more experience with college than their freshman counterparts. They also have two more years of life experience, which might not sound like much but is about a 50 percent increase in the number of quasi-adult years they have lived.

Most colleges require all students to take the same set of core courses. Take those before committing to a major. This will give you the time and opportunity to get a feel for what you like and where your talents lay.

Of course there is more to an education than a paycheck. If your dream is to educate children or to work in any of the lesser paying fields, go with God. But do so with open eyes. A quarter of a million dollar investment is not something to be made without clear and sober forethought.

And if you choose to make that investment but then find you can’t earn enough to afford your student loans, do not turn to the government to rescue you. With the freedom to choose your own path comes the responsibility to live with the consequences. Choose wisely.