“You’re late,” Mr. Rallis barks at me.

I look up at the clock. My classmates are sitting motionless with their textbooks open in front of them. It’s my turn to say something.

My usual chair waits for me in its usual spot. I walk to it and sit down to the same graffiti on the desk. Mr. Rallis stays focused on me. I look up into his small, glittering eyes.

“Did you bring your textbook to class, Serena?” he asks.

“Um …” I zip open my backpack, and sure enough, there is my calculus textbook, which has just traveled to Los Angeles and back. I take it out and put it on my desk, and we all stare at it, an artifact from a bygone era. I haven’t washed my hair since East St. Louis, haven’t brushed it since the bathroom in Albany, and there’s a big three-day-old coffee stain all over my T-shirt, which is Bo’s. If it weren’t for the fact that I’m also wearing Bo’s jacket, I could be easily persuaded that I made the whole thing up.

“Take out your homework,” Mr. Rallis directs.

“Homework,” I repeat. I notice that everyone else has their homework out, just like they do at the beginning of every class.

“Miss Velasco, did you do the problems that were assigned to you over spring break?”

While Mr. Rallis stares at me, I spool through my spring break. It flows through my mind in no particular order, the long miles of America through the dirty windows of the bus, the club in LA where Grimshaw worked, the guy at the bus station in Chicago who told me that people in St. Louis murdered each other for twenty bucks.

“No, I’m afraid I didn’t get to it, Mr. Rallis.”

“Nine days of vacation, and you couldn’t manage sixteen math problems?”

“Um, no, I didn’t get to it. I’m sorry.”

“Don’t feel sorry for me, miss,” he yells, clumping up and down aisles. “I’m not the one getting a zero. You’re not off to a particularly good start, here. You don’t want to get knocked off your perch, do you?”

“I can get it to you tomorrow,” I offer.

“Ah.” Mr. Rallis stops and puts his finger in the air. “Aha. Tomorrow, she says. Mañana. So. Ten days is the magic number, is it? X equals ten. Not nine, but ten. Ah yes, the precision, the exactitude, of math. If only vacation were ten days long instead of nine, there would be no problem. Is that it?” His sarcasm washes over me and sinks in like the next wave on the beach.

“Mr. Rallis, I don’t think I’m the one with the problem.”

He spins on his heel and stares at me. He points at the door. “Get out!”