Simon falls into step beside me as I move against the flow of students heading for the exit. “It’s a public service,” he says with a dismissive wave. “You tutor Reggie Crawley, don’t you?

Wouldn’t you rather know he has a camera in his bedroom?”

I don’t bother answering. Me getting anywhere near the bedroom of perpetual stoner Reggie Crawley is about as likely as Simon growing a conscience.

“Anyway, they bring it on themselves. If people didn’t lie and cheat, I’d be out of business.” Simon’s cold blue eyes take in my lengthening strides. “Where are you rushing off to? Covering yourself in extracurricular glory?”

I wish. As if to taunt me, an alert crosses my phone: Mathlete practice, 3 p.m., Epoch Coffee. Followed by a text from one of my teammates: Evan’s here. Of course he is. The cute Mathlete— less of an oxymoron than you might think— seems to only ever show up when I can’t.

“Not exactly,” I say. As a general rule, and especially lately, I try to give Simon as little information as possible. We push through green metal doors to the back stairwell, a dividing line between the dinginess of the original Bayview High and its bright, airy new wing. Every year more wealthy families get priced out of San Diego and come fifteen miles east to Bayview, expecting that their tax dollars will buy them a nicer school experience than popcorn ceilings and scarred linoleum.

Simon’s still on my heels when I reach Mr. Avery’s lab on the third floor, and I half turn with my arms crossed. “Don’t you have someplace to be?”

“Yeah. Detention,” Simon says, and waits for me to keep walking. When I grasp the knob instead, he bursts out laughing.

“You’re kidding me. You too? What’s your crime?”

“I’m wrongfully accused,” I mutter, and yank the door open.

Three other students are already seated, and I pause to take them in. Not the group I would have predicted. Except one.

Nate Macauley tips his chair back and smirks at me. “You make a wrong turn? This is detention, not student council.”

He should know. Nate’s been in trouble since fifth grade, which is right around the time we last spoke. The gossip mill tells me he’s on probation with Bayview’s finest for . . . something.

It might be a DUI; it might be drug dealing. He’s a notorious supplier, but my knowledge is purely theoretical. “Save the commentary.” Mr. Avery checks something off on a clipboard and closes the door behind Simon. High arched windows lining the back wall send triangles of afternoon sun splashing across the floor, and faint sounds of football practice float from the field behind the parking lot below.

I take a seat as Cooper Clay, who’s palming a crumpled piece of paper like a baseball, whispers “Heads up, Addy” and tosses it toward the girl across from him. Addy Prentiss blinks, smiles uncertainly, and lets the ball drop to the floor. The classroom clock inches toward three, and I follow its progress with a helpless feeling of injustice. I shouldn’t even be here. I should be at Epoch Coffee, flirting awkwardly with Evan Neiman over differential equations.

Mr. Avery is a give-detention-first, ask-questions-never kind of guy, but maybe there’s still time to change his mind. I clear my throat and start to raise my hand until I notice Nate’s smirk broadening. “Mr. Avery, that wasn’t my phone you found. I don’t know how it got into my bag. This is mine,” I say, brandishing my iPhone in its melon-striped case.

Honestly, you’d have to be clueless to bring a phone to Mr. Avery’s lab. He has a strict no-phone policy and spends the first ten minutes of every class rooting through backpacks like he’s head of airline security and we’re all on the watch list. My phone was in my locker, like always.

“You too?” Addy turns to me so quickly, her blond shampoo-ad hair swirls around her shoulders. She must have been surgically removed from her boyfriend in order to show up alone.

“That wasn’t my phone either.”

“Me three,” Cooper chimes in. His Southern accent makes it sound like thray. He and Addy exchange surprised looks, and I wonder how this is news to them when they’re part of the same clique. Maybe überpopular people have better things to talk about than unfair detentions.

Maybe überpopular people have better things to talk about than unfair detentions.

“Somebody punked us!” Simon leans forward with his elbows on the desk, looking spring-loaded and ready to pounce on fresh gossip. His gaze darts over all four of us, clustered in the middle of the otherwise empty classroom, before settling on Nate. “Why would anybody want to trap a bunch of students with mostly spotless records in detention? Seems like the sort of thing that, oh, I don’t know, a guy who’s here all the time might do for fun.”

I look at Nate, but can’t picture it. Rigging detention sounds like work, and everything about Nate — from his messy dark hair to his ratty leather jacket — screams Can’t be bothered. Or yawns it, maybe. He meets my eyes but doesn’t say a word, just tips his chair back even farther. Another millimeter and he’ll fall right over.

Cooper sits up straighter, a frown crossing his Captain America face. “Hang on. I thought this was just a mix-up, but if the same thing happened to all of us, it’s somebody’s stupid idea of a prank. And I’m missing baseball practice because of it.” He says it like he’s a heart surgeon being detained from a lifesaving operation.

Mr. Avery rolls his eyes. “Save the conspiracy theories for another teacher. I’m not buying it. You all know the rules against bringing phones to class, and you broke them.” He gives Simon an especially sour glance. Teachers know About That exists, but there’s not much they can do to stop it. Simon only uses initials to identify people and never talks openly about school.

“Now listen up. You’re here until four. I want each of you to write a five-hundred-word essay on how technology is ruining American high schools. Anyone who can’t follow the rules gets another detention tomorrow.”

“What do we write with?” Addy asks. “There aren’t any computers here.” Most classrooms have Chromebooks, but Mr. Avery, who looks like he should have retired a decade ago, is a holdout. Mr. Avery crosses to Addy’s desk and taps the corner of a lined yellow notepad. We all have one. “Explore the magic of longhand writing. It’s a lost art.”

Addy’s pretty, heart-shaped face is a mask of confusion. “But how do we know when we’ve reached five hundred words?”

“Count,” Mr. Avery replies. His eyes drop to the phone I’m still holding. “And hand that over, Miss Rojas.”

“Doesn’t the fact that you’re confiscating my phone twice give you pause? Who has two phones?” I ask. Nate grins, so quick I almost miss it. “Seriously, Mr. Avery, somebody was playing a joke on us.”

Mr. Avery’s snowy mustache twitches in annoyance, and he extends his hand with a beckoning motion. “Phone, Miss Rojas. Unless you want a return visit.” I give it over with a sigh as he looks disapprovingly at the others. “The phones I took from the rest of you earlier are in my desk. You’ll get them back after detention.”

Addy and Cooper exchange amused glances, probably because their actual phones are safe in their backpacks. Mr. Avery tosses my phone into a drawer and sits behind the teacher’s desk, opening a book as he prepares to ignore us for the next hour. I pull out a pen, tap it against my yellow notepad, and contemplate the assignment. Does Mr. Avery really believe technology is ruining schools? That’s a pretty sweeping statement to make over a few contraband phones.

Maybe it’s a trap and he’s looking for us to contradict him instead of agree. I glance at Nate, who’s bent over his notepad writing computers suck over and over in in block letters. It’s possible I’m overthinking this.