I entered into parenthood duly warned: You will experience shocking new heights of love and depths of vulnerability, everyone said, but do not worry, your heart will expand accordingly.

I received no such caution when I became a teacher.

No one took me aside to tell me about the dangers I would face caring about so many children. My heart can accommodate the love; that is not the problem. The problem is the vulnerability.

A few years after I started teaching English and Latin at a small New Hampshire middle school, the drowning dreams began: I gather my class on a frozen pond in New Hampshire for a lesson on Robert Frost’s wintertime poetry, ask them to close their eyes and envision “The way a crow shook down on me the dust of snow from a hemlock tree,” or listen for the “crystal shells shattering and avalanching on the snow crust.” As we stand on the cracked ice, it begins to give way, melting to slush under our feet.

I do what any born and bred New Englander would: I order my students to fall flat, spreading their arms and legs as wide as they can over the surface of the pond.

They all fall at once, scattered across the gray pond like a flock of frozen snow angels. As the ice disintegrates beneath them, slush becomes water, and they sink below the surface. I dive into the frigid water to gather them up, sputtering and heaving onto the safety of the frozen shore.

As anxious as this dream used to make me, the shooting at Sandy Hook Elementary School in Newtown, Conn., prompted the worst of my nocturnal horror shows.

Entire staff meetings were given over to the hypothetical what-ifs of locked-out students, incomplete head counts and multiple shooters. We would probably never need to use this information, we reassured ourselves, but you know, just in case.

These drills and planning sessions caused me more anxiety than they alleviated, because where other schools had access to lockable storage closets and libraries, my school contained no such space. I taught in a temporary trailer back then, a three-classroom double-wide equipped with one toilet, two small offices and four exterior doors.

My classroom door did not lock, and the closet could hold two or three of my smallest students in the narrow space below the shelves of novels and textbooks. The lockers were too small to hide most of the kids, and although the bathroom locked, we could fit 15, maybe 18 children in there, tops.

When the shooting nightmares started, my subconscious mind proved surprisingly resourceful: I usher the children out the rear door of my classroom, pry a flap of silver insulation away from the heavy-duty staples that hold it against the base of the trailer and burrow the children deep underground in a trench I had prepared ahead of time, just for this purpose. Once the children are safely concealed underground, I cover them with soil, sprinkling the last of it all around to disguise the hole. As shots ring out over my head in the classroom we had just occupied, I stand guard over my students, hidden under the last of the loose insulation, praying the gunman will not hear my ragged, panicked breaths through the trailer floor.

Once upon a time, there were ample intervals between school shootings for teachers to relax, enough time and perspective to remind ourselves just how unlikely it is that a man with a gun will pierce the safety of our classroom doors.

These days, it is hard to keep up. We pledge to #alwaysremember, #neverforget, but as the body count rises, I can no longer remember all the victims’ names, and I am tempted to let myself forget, if only out of self-preservation.

For the past 4 1/2 years, I have taught writing part-time in an inpatient drug and alcohol rehab program for adolescents. I mistakenly assumed my heart would be safe in this classroom of ornery addicts, that their combative, disruptive behavior would allow for some emotional distance. Besides, I reasoned, I would only teach them for one to three months, depending on their insurance, barely enough time to get to know them, let alone get attached.

The adoption dreams began less than a month after I started the job. Many teachers have these, I think; teach long enough and most of us subconsciously test out the idea of bringing home a student or two.

I do not know what I was thinking; of course I fell in love. I underestimated their vulnerability, their transparent need to be loved and the sheer weight of their emotional need. Many of my students live in group or foster homes. Some care for their addicted parents and raise their younger siblings. Some cannot be discharged because they simply have nowhere to go.

In my dreams, I have adopted nearly all of them, even the ones who call me names and refuse to write for me. I bring them home, feed them, keep them warm — like abandoned baby rabbits, except with attitudes, pimples and substance abuse.

As their writing teacher, I encourage my students to write through their anxiety and create strategies for dealing with the triggers they will face once they graduate from rehab and return to the families and communities where they became addicted in the first place. For opiate addicts, this transition out of rehab is particularly dangerous, as a dose of heroin that was barely enough to get them high a month ago could very well kill them in their newly detoxed state.

To manage my feelings of fear and helplessness, my subconscious got to work, combining the practical skills I have learned during EpiPen training with my new knowledge about the importance of prompt Naloxone administration in an overdose situation.

When I originally learned how to use an EpiPen, we practiced on oranges. It is the closest human analogue, according to the school nurse who ran our training.

In my dreams, however, the injectors hold Naloxone, and she trades out oranges for crab apples. “They’re harder, and that heroin addicts’ skin is tough,” she explains.

Once we have practiced on the apples, jabbing with all our strength to pierce through that tough skin, she calls for the students. To truly master the technique, she says, we will have to practice on them. But avoid their bones, she emphasizes, because if our needles get stuck in their bones, we will never get them out.

When I am asked what it means to be a teacher, I often refer to my students as “my kids,” and that can be confusing, given I also have two sons. I never have to explain myself to other teachers, however. They get it. We cannot do our jobs without surrendering, at least a little, to the helplessness, the vulnerability and the love.

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