Challenge: Jay and chalkboard.

Eighteen-year-old Jay Walker slumped over his desk, groaning softly. He was all alone in the college classroom where he usually took Calculus I, surrounded by empty desks. During class this room would be filled with more than twenty students, running the full range from bored to anxious as they tried to decipher the professor's lectures. Right now, however, it was just Jay, studying his brains out.

College was rough. The classes weren't so bad overall, but this calculus course was murder. He'd been in college for almost two months and hadn't made a single friend. The only person he really knew was his roommate Cole, and they didn't get along so great. Cole was always eating loudly and playing lame music, making it impossible for Jay to study, and Jay was too shy to ask for him to stop. That was why he studied here, in the empty calculus classroom.

Sighing, he crossed his eyes at the calculus scribbles half an inch away from his eyeballs. He tried to mumble some formulas by heart, but it created an effect rather like counting sheep, and within moments he had dozed off with his forehead still on his notebook.

He woke up a few minutes later to the sound of the door clicking shut. He bolted upright, gasping. Had someone been in the room?! He looked frantically around at his belongings, felt for his phone. His ma had warned him about keeping a close eye on his possessions on-campus!

But nothing seemed to be stolen. Now filled with curiosity, Jay scrambled to his feet and poked his head out into the hallway. He heard distant footsteps trotting away somewhere in the building, but he knew whoever-it-was had to be too far away to catch.

Feeling vaguely creeped-out, Jay returned to his desk. What had all that been about? Had it just been a janitor going around closing doors?

Then he stopped. On the side chalkboard, the one the teacher rarely used, was a strange upside-down L shape. Underneath were 8 dashes, and underneath those was the entire alphabet, neatly printed. Jay broke into a smile of recognition. A game of Hangman!

Stepping over to the chalkboard, he studied the eight dashes. Recalling the tactics he'd learned as a kid, he drew a circle around E, the most common letter in the English language. Then he went back to studying as if nothing had happened . . . Only every now and then he snuck a glance over to the silent chalkboard, wondering who had started the game with him.

The next day was a Wednesday, so Jay didn't have Calculus (a Tuesday-Thursday class). Still, he found an excuse to walk through the math building on his way home; it's not like he had any friends to ask him why. He peeked into the Calculus classroom and smiled: there was a big E drawn on the third of the eight dashes. Slipping into the room, he circled T as his next guess.

Just as he was about to leave, he realized that tomorrow would be another Calculus class. What if the professor or someone else erased the game-in-progress? He'd never find out what the word was supposed to be!

For a moment he hesitated, wondering if he dared abuse the powers of chalkboard law. Then he decided he dared. He picked up the chalk again and scrawled in the corner a large, bold "D.N.E."—Do Not Erase.

He got to class early the next day. The professor was already there setting up, and Jay saw to his relief that the game of Hangman was still there. He sat down at his desk and snuck a closer look at the game. There was no T written on the eight dashes. Instead the first part of the man being hanged, the head, had been drawn in. A few more wrong guesses and that guy was a goner. For good measure, off to the lower right Jay's mysterious opponent had scrawled the word "Ha!" Jay quickly buried his nose in his calculus textbook to hide the grin spreading across his face. Oh, it was on.

Jay kept peeking into the classroom every day, sometimes more than once a day, checking if the game had progressed. Sometimes it hadn't, and he'd feel a little wave of disappointment, but more often it had. By Saturday he'd figured out the word. Triumphantly he wrote in the last few letters of FRESHMAN, and scribbled his own little "Ha!" by the finished game.

After a moment's hesitation, he added a note in tiny chalk-scribbled print: "I'm a freshman! Are you too?"

The next time he saw the chalkboard, the old game had been erased and a new game was set up, this one with nine dashes. And down in the corner, in equally small print, just the word "yeah."

Over the next few weeks, Jay played multiple games of Hangman against his new invisible friend. They both slipped little notes into the games, teasing each other over victories, anticipating fall break, groaning over difficult exams. A couple of times Jay asked if they could meet or exchange names, but his opponent never answered those inquiries. Still, it was nice to feel like he had a friend out there, at least sort of.

"I'm having fun," he wrote one day. "Thanks for doing this."

The next time he checked, the answer was, "No problem. You looked lonely."

"I was," Jay wrote back. "Thanks."

He grew a little less lonely as the semester went on, though. Ironically, he made his first face-to-face friends over the game of Hangman too. The other students in the class soon took notice of the ongoing games on the side chalkboard, and they became a hot pre-class discussion topic. Jay shyly joined into the conversations now and then, although he never let on that he was the one playing half the game.

One day the professor wanted to use the side chalkboard, however. He looked over the current game with its giant D.N.E., made an ironic comment, and left it alone. Jay blushed so hard he could feel it, and between that and his smile he knew it would be hard for his classmates not to notice.

Sure enough, after class a girl called Nya asked if he was the one playing chalkboard Hangman. Jay said yes, and ventured to ask if she was the other player. Nya laughed and said no, she'd never played Hangman before. Jay offered to teach her, and they hit it off from there on out. Soon he also met her older brother Kai, a junior, and from there he just kept making new friends. Slowly he began to feel like he fit in at college; he even grew less timid around his roommate Cole (although this mostly just meant that they squabbled more).

As the end of the semester approached, Jay approached the Calculus classroom with a bittersweet feeling. He still hadn't found the identity of his mystery friend, and next semester he wouldn't be taking Calculus anymore. They'd probably never interact again. He was going to check if a new game had been set up—if it was, it might be their very last.

As he neared the classroom, however, Jay froze. The lights were on, and someone was moving around inside. There was an idle humming and the whisper of chalk. Eyes widening, Jay stepped ever so quietly up to the door and placed his hand on the knob. He'd waited long enough; now he and his first college friend were finally going to meet.