'To Catch a Falling Leaf' by Kevlin Henney

They say it's good luck to catch a falling leaf. Some say it will bring you a day of luck and happiness, others say a month. A few say you should make a wish when you catch it.

"Is no such thing as luck." Mr Korzhakov might not believe in it, but I could really do with some. Parents are talking divorce, someone nicked my bike, I failed last week's applied maths test, Milly dumped me and Leona just looks right through me.

"What people call luck is just experience of the one in probability of one in N. If you bet on heads you have one in two chance. If you get heads you feel lucky, if you don't you don't. If you bet on rolling three, you have one in six chance. If you roll three you feel lucky, if you don't you don't. And so on." Mr Korzhakov sweetened dry lessons in probability and stats with a rambling preamble before moving on to a syllabus that invited sleep and doodles.

"Not if you use my dice!" Aaron spilt gaming dice over his desk. Mr Korzhakov walked over and picked up a d20, holding it close enough to peer over his bifocals.

"Icosahedron? Pure maths is Mr Brown, Aaron. But of course, this is one in twenty. Bigger N, luckier you feel if you get it. Is why people like to play lottery — N very big!"

"What about bad luck?" I asked.

"Ah, good question, Jim. Is still luck, just different type. You want one-in-six bad luck? Play Russian roulette with six-shooter! You buy lottery ticket? Have more chance of being hit by car than winning! Good or bad, luck is just name we give to events we notice but not see bigger picture, when we hope rather than predict."

It's Mr Korzhakov first this morning. I'm about to head through the school gates when I spot Leona on the other side of the road. I slow to match her pace, to think of something to say, to think of a reason to talk to her.

I spot a leaf twist in the breeze and fall from the sycamore overhanging the road. The breeze is gentle enough that I can tell how and where the leaf is going to fall. Golden and crisp, touched by a reluctant autumn sunrise, it seems to hang in the air for a moment, like an invitation. Luck is on my side. I run, crossing over to catch it before it hits the road, my wish at the ready.

But it falls through my hand. Passes through it. Right through it. As if it didn't exist.

I look up. Leona is standing next to me, staring right through me, her mouth frozen, open, covered by her hand. I turn to see a car, a shocked driver fumbling an emergency call on his mobile, teachers and pupils running towards the gate, a fallen boy on the road wreathed in uncaught autumn leaves.