My sophomores are strikingly, shockingly quiescent as they sit, recline and huddle together in the corner. It is eerily quiet, quiz-and-exam-time quiet, but quieter: no soft sounds of writing or pages turning. We are hiding as we have been instructed to do during this “code red” drill. I feel sadness and a bit of irrational dread. I think, “It has come to this.” I think about how otherworldly this motionless, quiet classroom scene is.

All but one student look like puppies sleeping after nursing, all crammed in, sometimes awkwardly, to their mother. But there is no mother, only me. They are encircled by a corner formed by a wall, a floor and a large teacher’s desk. I stand in the opposite corner, as instructed, hoping to not be seen through the large windows to outside. There are no window blinds.

I locked the door when the drill was announced, and a pre-assigned student taped a posterboard blind over the door window. I wonder why we had not attempted to build a makeshift barricade to block entrance through the door. I wonder why we did not open the emergency door and run outside. It makes perfect sense, but that is not part of the “code red” protocol.

For five minutes, maybe 10, my students huddle quietly. One or two might be dozing. They had joked about falling asleep before the silence fell.

We were pretending, days after the Parkland, Florida, shooting, that someone with a gun was trying to kill us.

The biggest troublemaker in class climbs inside my small coat closet and shuts the small door. He must be contorted in an awkwardly comical, perhaps painful, position. But it is always worth being the outlier if he can get a rise out of me. He cannot, not today with so much on my mind. The lives of my students in this mock attack are on my mind. I look at the small coat closet and shake my head. He, more than anyone else in this class, has never been this quiet for so long.

Maybe the silver lining is this absence of almost-daily teen challenges to my authority. Maybe another silver lining is the lack of disruptions that distract the well-behaved students struggling to learn. All are perfectly behaved.

The drill takes forever. The impossible silence continues. This is the most serious attention to the matter at hand I have ever seen.

I do not know if my students are scared, but they are paralyzed with intention. Or maybe they are just feeling comfortable. Maybe one or two of them are asleep. The image, though, is unforgettable: 15 students sardined together in the space of a twin bed mattress. They are that tightly crammed in, silent and motionless, a heap of human life. They all deserve to live.

Finally, the intercom announces the end of the drill. The silence breaks; we unfreeze. And my pedagogy now contains the phrase “code red.”