Walk around a college university bookstore and you just might see this Apple advertisement for a Mac with the following headline: “It makes the best years of your life even better.”

(Valerie Strauss/Washington Post)

Hmmm. Apple is supposed to be smarter than that.

It has become an all-too common notion that college is — or, at least, is supposed to be — the best time in life (at least for the people lucky enough to go).

So said the opening lines of the 2011 article in Forbes magazine that ranked the so-called best 650 undergraduate schools: The best years of life are also among the most expensive. Choose with care.

So said the “Today Show’s” Web site when it listed the Princeton Review’s top picks in categories such as athletic facilities, food and dorms: “Here are the Princeton Review’s top five picks in the categories that make college years the best years in life.”

The notion is so ingrained in the popular psyche that Psychology Today published an article in 2010 with the headline: “College — Is It Really the Best Time of Our Lives?”

To be sure, going to college is a big moment in life, and, certainly, for some people, college is the best time in their life. But apart from the sad notion that the years from around 18 to 22, 23 or 24 are the high point in a life, it remains true for many, many students, that college isn’t at all what it’s cracked up to be in the “time of your life” department.

Right now millions of high school seniors are deciding where they will go to college, and students already in college are gearing up to finish up their year with final papers and exams.

That makes it a good time to remind everybody that while college can and should be marvelous, sometimes even often, it isn’t — and that is just as normal as anything else.

“If you are having difficulty, you imagine you are the only one in that category,” said David Leibow, who is on the psychiatry faculty of the Columbia University College of Physicians & Surgeons and the author of the 2010 book “What to Do When College is Not the Best Time of Your Life.”

“I see a lot of college students and it’s very clear to me that it’s not clear to them how common their particular issue is,” he said. “And the fact that nobody knows what normal is makes them feel even worse. They feel isolated and ashamed and because they are ashamed they don’t seek help.”

And for many, if not most — definitive numbers are impossible to come by — college is as daunting as it is wonderful. For starters, college can be an enormous financial trial for young people from disadvantaged and even middle-class backgrounds. Many students have to work throughout college — having little or no “spare time” to have fun — and sometimes take semesters off because they can’t afford the tuition. Others find they can’t afford to finish.

How many? Nobody knows for sure because the available data is flawed, says the college completion section of the Chronicle of Higher Education Web site, which has a great collection of statistics that are available for each state and individual schools.

Here are statistics — that the Chronicle took from the U.S. government’s National Center for Education Statistics — for the 4.3 million freshmen who started college in fall 2004. Roughly 2.1 million of them didn’t “officially” graduate — but that number is way off, because it includes both dropouts and transfer students who started at one college and actually graduated from another. Meanwhile, another 1.2 million of the 4.3 million aren’t even tracked; many are part-time students whom the government doesn’t follow.

Then there is the large segment of kids who become depressed at varying levels during college, sometimes during freshmen year but in later years too. The National Institute of Mental Health reported that in 2009 a nationwide survey of college students at two- and four-year institutions found that nearly 30 percent of college students reported feeling “so depressed that it was difficult to function” at some time in the previous year. And that doesn’t include the kids who can function but are miserable.

So where did we get the idea college is the best time in life? Perhaps because it is true that for many people, college is the first time they are living away from their families and live essentially independently. It is a time, too, that students can experiment with their own identities and images in a new environment. Adults tend to forget the pain associated with getting through college and only remember the good times, thus mythologizing that period in their own — and, perhaps, children’s minds.

What adults should be telling students who are in college or who are going to be is that college can and hopefully is or will be wonderful, but there is every chance that they will encounter difficulties of some sort that require outside help, and that they shouldn’t be ashamed to get it. For starters, here’s a primer on depression in college.

There are, of course, those who look further back, to high school, as being the best time in their lives but let’s just not go to that sad place.

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