Miss Sidley was her name, and teaching was her game.

She was a small woman who had to stretch to write on the highest level of the blackboard, which she was doing now. Behind her, none of the children giggled or whispered or munched on secret sweets held in cupped hands. They knew Miss Sidley's deadly instincts too well. Miss Sidley could always tell who was chewing gum at the back of the room, who had a beanshooter in his pocket, who wanted to go to the bathroom to trade baseball cards rather than use the facilities. Like God, she seemed to know everything an at once.

She was graying, and the brace she wore to support her failing back was limned clearly against her print dress. Small, constantly suffering, gimleteyed woman. But they feared her. Her tongue was a schoolyard legend. The eyes, when focused on a giggler or a whisperer, could turn the stoutest knees to water.

Now, writing the day's list of spelling words on the board, she reflected that the success of her long teaching career could be summed and checked and proven by this one everyday action: she could turn her back on her pupils with confidence.

“Vacation,” she said, pronouncing the word as she wrote it in her firm, no-nonsense script. “Edward, please use the word vacation in a sentence.”

“I went on a vacation to New York City,” Edward piped. Then, as Miss Sidley had taught, he repeated the word carefully. “Vay-cay-shun.”

“Very good, Edward.” She began on the next word.

She had her little tricks, of course; success, she firmly believed, depended as much on the little things as on the big ones. She applied the principle constantly in the classroom, and it never failed.

“Jane,” she said quietly.

Jane, who had been furtively perusing her Reader, looked up guiltily.

“Close that book right now, please.” The book shut; Jane looked with pale, hating eyes at Miss Sidley's back. “And you will remain at your desk for fifteen minutes after the final bell.”

Jane's lips trembled. “Yes, Miss Sidley.”

One of her little tricks was the careful use of her glasses. The whole class was reflected in their thick lenses and she had always been thinly amused by their guilty, frightened faces when she caught them at their nasty little games. Now she saw a phantomish, distorted Robert in the first row wrinkle his nose. She did not speak. Not yet. Robert would hang himself if given just a little more rope.

“Tomorrow,” she pronounced clearly. “Robert, you will please use the word tomorrow in a sentence.”

Robert frowned over the problem. The classroom was hushed and sleepy in the late-September sun. The electric clock over the door buzzed a rumor of three o'clock dismissal just a half-hour away, and the only thing that kept young heads from drowsing over their spellers was the silent, ominous threat of Miss Sidley's back.

“I am waiting, Robert.”

“Tomorrow a bad thing will happen,” Robert said. The words were perfectly innocuous, but Miss Sidley, with the seventh sense that all strict disciplinarians have, didn't like them a bit. “Too-mor-row,” Robert finished. His hands were folded neatly on the desk, and he wrinkled his nose again. He also smiled a tiny side-of-the-mouth smile. Miss Sidley was suddenly, unaccountably sure Robert knew about her little trick with the glasses.

All right; very well.

She began to write the next word with no word of commendation for Robert, letting her straight body speak its own message. She watched carefully with one eye. Soon Robert would stick out his tongue or make that disgusting finger-gesture they all knew (even the girls seemed to know it these days), just to see if she really knew what he was doing. Then he would be punished.

The reflection was small, ghostly, and distorted. And she had all but the barest comer of her eye on the word she was writing.

Robert changed.

She caught just a flicker of it, just a frightening glimpse of Robert's face changing into something… different.

She whirled around, face white, barely noticing the protesting stab of pain in her back.

Robert looked at her blandly, questioningly. His hands were neatly folded. The first signs of an afternoon cowlick showed at the back of his head. He did not look frightened.

I imagined it, she thought. I was looking for something, and when there was nothing, my mind just made something up. Very cooperative of it. However.

“Robert?” She meant to be authoritative; meant for her voice to make the unspoken demand for confession. It did not come out that way.

“Yes, Miss Sidley?” His eyes were a very dark brown, like the mud at the bottom of a slow-running stream.

“Nothing.”

She turned back to the board. A little whisper ran through the class.

“Be quiet!” she snapped, and turned again to face them. “One more sound and we will all stay after school with Jane!” She addressed the whole class, but looked most directly at Robert. He looked back with childlike innocence: Who, me? Not me, Miss Sidley.

She turned to the board and began to write, not looking out of the corners of her glasses. The last half-hour dragged, and it seemed that Robert gave her a strange look on the way out. A look that said, We have a secret, don't we?

The look wouldn't leave her mind. It was stuck there, like a tiny string of roast beef between two molars – a small thing, actually, but feeling as big as a cinderblock.

She sat down to her solitary dinner at five (poached eggs on toast) still thinking about it. She knew she was getting older and accepted the knowledge calmly. She was not going to be one of those old-maid schoolmarms dragged kicking and screaming from their classes at the age of retirement. They reminded her of gamblers unable to leave the tables while they were losing. But she was not losing. She had always been a winner.

She looked down at her poached eggs.

Hadn't she?

She thought of the well-scrubbed faces in her third-grade classroom, and found Robert's face most prominent among them.

She got up and switched on another light.

Later, just before she dropped off to sleep, Robert's face floated in front of her, smiling unpleasantly in the darkness behind her lids. The face began to change.

But before she saw exactly what it was changing into, darkness overtook her.

Miss Sidley spent an unrestful night and consequently the next day her temper was short. She waited, almost hoping for a whisperer, a giggler, perhaps a note-passer. But the class was quiet – very quiet. They all stared at her unresponsively, and it seemed that she could feel the weight of their eyes on her like blind, crawling ants.

Stop that! she told herself sternly. You're acting like a skittish girl just out of teachers' college!

Again the day seemed to drag, and she believed she was more relieved than the children when the last bell rang. The children lined up in orderly rows at the door, boys and girls by height, hands dutifully linked.

“Dismissed,” she said, and listened sourly as they shrieked their way down the hall and into the bright sunlight.

What was it I saw when he changed? Something bulbous. Something that shimmered. Something that stared at me, yes, stared and grinned and wasn't a child at all. It was old and it was evil and…

“Miss Sidley?”

Her head jerked up and a little Oh! hiccupped involuntarily from her throat.

It was Mr Hanning. He smiled apologetically. “Didn't mean to disturb you.”

“Quite all right,” she said, more curtly than she had intended. What had she been thinking? What was wrong with her?

“Would you mind checking the paper towels in the girls' lav?”

“Surely.” She got up, placing her hands against the small of her back. Mr Hanning looked at her sympathetically. Save it, she thought. The old maid is not amused. Or even interested.