College, like youth, is wasted on the young. This is not merely idle philosophizing on my part, but a conclusion arrived at from hard-won experience. Last year, nearly a decade after graduating from college, I spent two illicit semesters back in school--sneaking into classes, playing intercollegiate sports, and getting drunk in the dorms. This year of studying dangerously began innocently enough. My girlfriend was finishing up grad school at an Ivy League university; shortly after I moved in with her, on the outskirts of campus, I began reminiscing about my own college days. Idly flipping through her course catalog, inspiration struck: As long as I'm here, I thought ...

I ventured out onto campus a day early to scope out classrooms, striking from my list any that looked too small for me to hide in the crowd. That night, perched on a bar stool at the local watering hole, I tried on false identities-- literature grad student, American Studies fellow, returning G.I.--that I might use to parry questions from suspicious teaching assistants or flirtatious coeds.To my relief and disappointment, my classmates couldn't have cared less about me. Or, for that matter, about what we were learning in class. They were good enough students, mind you, but purely perfunctory ones. For my part, I took to being a fake student with a zeal I never knew as a real, tuition-paying one. I bought the books and course packets. I devoured the assigned readings. I dreaded midterm and finals weeks--not because I had to take the tests, but because I couldn't. I even rubbed patched elbows with faculty members at dorm teas, downing those tasty little finger sandwiches by the handful and bluffing my way through conversations on such esoteric topics as Nabokov's career in lepidoptery. Before long, I began tempting fate by sitting in on smaller classes.

It was at the Divinity School that I nearly pushed my luck too far. Seeing 40 other students in the room on the first day of class, I was lulled into a false sense of security. They wouldn't know me from Adam, I figured. Then the professor arrived, strode to the front of the class, and welcomed everyone ... back? Evidently, I had stumbled into the continuation of a first semester class. To "get the juices flowing," the professor asked us each to think of our favorite and least-favorite passages from the Pauline letters and be ready to discuss them aloud. He then began calling on people, rapid-fire, at random: you in the red hat, you there with the scarf, you with the deer-caught-in-the- headlights look trying desperately to pass as an undergraduate. Mercifully, my prayers not to be called on were answered. I stumbled from the room, shaken but unrepentant.

A still more frightening cautionary tale presented itself in the form of a fellow faker I discovered on campus. Lucy (not her real name) was a tiny Asian woman with an angelic face and wild eyes who was oddly cagey when I asked her what program she was in. "That's a very personal question," she told me. My suspicions were confirmed when I found myself behind her in line for the gym one day. After Lucy disappeared around a corner, a woman barged into line and demanded to know how she had passed herself off. "She said she was a med student who forgot her ID," said the startled check-in desk attendant. "She's no medical student," said the woman, now fuming."But she's been thrown out of medical school buildings for posing as one." As the year wore on, I always wondered how my sister-in-deception was faring. One perfect spring day, I found out. As I walked across campus, I noticed a commotion in front of one of the university buildings where I often took classes. Moving closer, I saw Lucy, now handcuffed, being led out by university police and placed into the back of a patrol car.

I should have been scared straight, but, by then, I was in too deep.Inspired by the 1986 classic Back to School, starring Rodney Dangerfield as an unrefined millionaire who enrolls in college and winds up joining the diving team, I had joined the water polo team. It was shockingly easy. At the gym, I'd noticed postings for the various club sports. I simply e-mailed the captain, told him I was a grad student who had played in college (that last part, at least, was true), and I was in. When I revealed my true identity, a few practices later, nobody seemed to mind much. (Note to rules sticklers: I only played in non-league games.)

With the help of the water polo guys, my regression approached the level of Will Ferrell's in Old School--the more recent, and even funnier, old-guys-go-to- college flick--particularly on the night of freshman initiation. Along with the other "frosh," I began the night by having kamikaze shots poured straight from the bottle into my mouth. The details of what came next are a bit of a blur, but I know for certain that I refereed a moonlit wrestling match between two upperclassmen in a campus courtyard, and that I was caught, along with the rest of the team--shirtless, sweaty, and sloshing drunk--having broken into the squash courts beneath the dorms.

I'd like to blame my age-inappropriate behavior on the alcohol. But the fact is, I relished the chance to run wild on campus with obnoxious undergrads again. There was so much that I envied about my teammates' youth: their unwritten futures, their swashbuckling tales of casual hook-ups, their seeming immunity to hangovers. But, on the long van rides back from tournaments, I was also reminded of the confusion and insecurity of the college-aged. We talked about girls, jobs, and the looming prospect of adult life. One teammate confessed to me that, as a writer, I was living his dream. But wait: Wasn't he living mine?

As water polo initiation passed from night into early morning, I sobered up and reality came back into focus. When my teammates began streaking, Frank-the- Tank-like, across campus, I pulled away from the pack and watched, somewhat wistfully, as they disappeared from view. But, on the giddy walk back to my apartment and girlfriend, I wasn't thinking about what I was missing out on, but rather what they were. I had to get home and to bed. After all, I thought to myself, I have class tomorrow.