Thief of Time

the cobbles of a plaza in a different city. So was the classroom. There were the cupboards, and the Nature Table, and the blackboard. But the walls had vanished.
    No one in the plaza paid the visitors any attention but, oddly, no one tried to walk into them either. The air was warmer, and smelled of sea and swamp.
    “Anyone know where this is?” said Miss Susan.
    “Ooo, me, miss, ooo, ooo…” Vincent could only stretch his body taller if his feet left the ground.
    “How about you, Penelope?” said Miss Susan.
    “Oh, miss ,” said a deflated Vincent.
    Penelope, who was beautiful, docile, and, frankly, dim, looked around at the thronged square and the whitewashed, awning-hung buildings with an expression close to panic.
    “We came here in Geography last week,” said Miss Susan. “City surrounded by swamps. On the Vieux River. Famous cookery. Lots of seafood…?”
    Penelope’s exquisite brow creased. The pigeon on Miss Susan’s desk fluttered down and joined the other pigeons prospecting for scraps among the flagstones, cooing very gently to them in pidgin pigeon.
    Aware that a lot could happen while people waited for Penelope to complete a thought process, Miss Susan waved at a clock on a shop across the square and said: “And who can tell me the time here in Genua, please?”
    “Ooo, miss, miss , ooo…”
    A boy called Gordon cautiously admitted that it might be three o’clock, to the audible disappointment of the inflatable Vincent.
    “That’s right,” said Miss Susan. “Can anyone tell me why it’s three o’clock in Genua while it’s twelve o’clock in Ankh-Morpork?”
    There was no avoiding it this time. If Vincent’s hand had gone up any faster it would have fried by air friction. “ Yes , Vincent?”
    “Ooo miss speed of light miss it goes at six hundred miles an hour and at the moment the sun’s rising on the rim near Genua so twelve o’clock takes three hours to get to us miss!”
    Miss Susan sighed.
    “Very good, Vincent,” she said and stood up. Every eye in the room watched her as she crossed over to the Stationery Cupboard. It seemed to have traveled with them and now, if there had been anyone to note such things, they might have seen faint lines in the air that denoted walls and windows and doors. And if they were intelligent observers, they’d have said: so…this classroom is in some way still in Ankh-Morpork and also in Genua, is it? Is this a trick? Is this real? Is it imagination? Or is it that, to this particular teacher, there is not much of a difference?
    The inside of the cupboard was also present, and it was in that shadowy, paper-smelling recess that she kept the stars.
    There were gold stars and silver stars. One gold star was worth three silver ones.
    The headmistress disapproved of those, as well. She said they encouraged Competitiveness. Miss Susan said that was the point, and the headmistress scuttled away before she got the Look.
    Silver stars weren’t awarded frequently, and gold stars happened less than once a fortnight, and were vied for accordingly. Right now Miss Susan selected a silver star. Pretty soon Vincent the Keen would have a galaxy of his very own. To give him his due, he was quite disinterested in which kind of star he got. Quantity, that was what he liked. Miss Susan had privately marked him down as Boy Most Likely To Be Killed One Day By His Wife.
    She walked back to her desk and laid the star, tantalizingly, in front of her.
    “And an extra special question,” she said, with a hint of malice. “Does that mean it’s ‘then’ there when it’s ‘now’ here?”
    The hand slowed halfway in its rise.
    “Ooo…” Vincent began and then stopped. “Doesn’t make sense, miss…”
    “Questions don’t have to make sense, Vincent,” said Miss Susan. “But answers do.”
    There was a kind of sigh from Penelope. To Miss Susan’s surprise, the face that one day would surely cause her father to have to hire bodyguards was emerging from its normal happy daydream and wrapping itself around an answer. Her alabaster hand was rising, too.
    The class watched expectantly.
    “Yes, Penelope?”
    “It’s…”
    “Yes?”
    “It’s always ‘now’ everywhere, miss?”
    “Exactly right. Well done! All right, Vincent, you can have the silver star. And for you, Penelope…”
    Miss Susan went back to the cupboard of stars. Getting Penelope to step off her cloud long enough even to answer a question was worth a star, but a deep philosophical