The road was so dark, and the night so foggy, that I could hardly see. My 16-year-old son Simon and I were in southwestern Virginia. Diamond-shaped warning signs about downhill grades and truck brakes flashed by. The sky was weirdly light along the horizon, but none of that seemed to translate to the highway that unfurled blackly ahead.

“Do you want me to drive?” Simon asked.

I was tired and the fog was dissipating, so I said yes and pulled off the road. We switched places in a silent gas station. As I buckled into the passenger seat, I considered the situation. We were only two hours into our first college visiting trip, but it seemed like we were living a pretty decent metaphor already. Look at us, I thought, as ghostly hills loomed, one after the other. He’s driving in the dark. I’m just along for the ride.

Since then, Simon and I have road-tripped to quite a few colleges, and I’ve come to see that the process of imagining a child’s next step is a little more complicated than switching seats. The progression includes nerve-racking ingredients like tests, log-in names, money and introspection. And if you’re the parent, you’ve reached a disquieting moment: Now, you understand that cliche about how fast they grow up. You can grab at their childhoods all you want, but they’re gone, water through your fingers. You’re no longer setting your jaw in the grocery line when someone tells you, “Oh, enjoy that baby! It goes by so quickly,” as your 2-year-old flings blueberries. Instead, you’re resisting saying those words to the dad you’ve allowed to go ahead of you in line, as he snatches the container from his screaming child’s hands.

When visiting colleges, you’re trying to see into the future. You do this despite the central lesson children have taught you: You can’t guess what comes next.

The trips are also about both of you being out of your element at the same time. At least with your first college-bound child, neither of you can pretend you’re already an old hand at this. For example, I learned I don’t do well on campus tours. We took one with a guide who, I felt, was too good at her job. The question-and-answer session went on for hours, because no one could stump her, and she was too kind to call a halt to the whole thing. One mother lobbed a query about requirements for junior physics majors who study abroad, and the guide had an answer. How many punches on a meal card? Can you switch majors midyear? Where does the club judo team practice? She knew it all, and the hands kept going up.

I swear I did not mean to sigh, but I guess I did. “Be good,” Simon said to me as I shifted from side to side. I saw a father and son exchange a look. That dad had had it, too, and actually rolled his eyes at me. I kind of widened mine back, as if I wasn’t rolling, too. I didn’t fool anyone, though. Simon gave me the wing, which is a family term for clocking someone with your elbow, and stared tolerantly ahead.

Our roles were up for grabs.

Traveling with Simon, I tend to eat as if I, too, am a 16-year-old ice hockey player. We both ordered giant hamburgers in a sticky-floored dive, and threw darts while they cooked. Simon’s first dart hit the bull’s eye, and the next two were pretty close. Then it was my turn. Let’s just say I didn’t have the same results, so Simon offered some advice.

“You have to believe in every dart you throw,” he said.

This seemed so koan-like and wise that I was taken aback. What 16-year-old says that? (Upon further reflection: What does that even mean?) But I tried. I stared at the board and imagined the dart going in. I threw, and my dart stuck, really close to the bull’s eye. The next one, too, and the one after that. Simon was on to something.

We began to take a different approach to visiting colleges, and sometimes picked up campus maps and walked around on our own. Simon wants to study engineering, and one building he found was brand new, sun-filled and dazzling, and we puttered around, looking in labs’ observation windows and trying out couches. We saw lathes, 3D printers, robotic arms. A lab manager we met in an elevator explained engineering majors to us, and watching him talk with Simon in his own vernacular—maker space, formula hybrid team, soldering workshop — I could suddenly see him at college. He belonged, both in language and space.

We got back into the car, had a rambling, pleasant conversation about various dogs we like, hikes we want to take, the plot of the Superman movie we’d watched in a Hampton Inn. Somewhere in North Carolina I found out Simon had picked up that sage-sounding line about believing in every dart you throw from a friend. But it was all right. Isn’t that what education’s all about? You learn something, use it, remember it, then pass it along at the right moment. Bull’s eye.

College visiting happens during a fraught time in a family’s life, which means it’s not that different from every other stage of raising children. In a roadside diner, I watched Simon eat eggs, pancakes, bacon and hash browns, which I’d also ordered. After lunch, I walked around to the passenger side of the car, but Simon, syrup-sleepy, asked me to drive.

We still need each other. There’s no such thing as going along for the ride.

Eliza McGraw is a Washington writer. She is the author of “Here Comes Exterminator!,” a book about the 1918 Kentucky Derby winner.

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