I had coveted this role for years; not because I had any particular interest in the Virgin birth, you understand, but because I wanted the adulation. I wanted to be surrounded by admiring eyes, even if they were parents, teachers, a few sheep and a donkey.
When the choosing came, I was the only one who put my hand up, and felt sure the role was mine. Unfortunately, I was horrendous to look at. Our teacher, ignoring my academic prowess, overlooked my lone hand, and chose Anne-Marie. She had straight, blonde hair, and you could rely on her to sit and look virginal, and not hassle Joseph to find her somewhere nicer to spend the night than the stable.
Now I'm the teacher, and I feel all the weight of my role as a chooser. I've realised it's a big responsibility. You don't just choose one person, you unchoose 29.
I don't think the spotlight should be the only place where you get to feel special. The run-up to Christmas seems to have an air of ruthlessness about it. It takes on the same inevitability as homework.
I prowl around the corridors, looking out for any misplaced Marys, any guests who feel unwanted. Wandering around, I think about Anne-Marie, and wonder what she's doing now. She's probably still someone's Christmas fairy, but that's ok with me. She'd look good with a tree stuck up her backside. Maybe she's an OFSTED inspector. She's definitely not up until all hours trying to make 30 politically-correct "Winter Festivities" cakes for her form, ripped off from some Delia Smith cookbook.
WAR 10 are unimpressed as I hand round my soggy end-of-term happiness cakes which also take into account that major world religions are celebrating special events. "These don't look like mince pies, Miss." I'm trying to make a present of my presence - talk about a screwed-up Scrooge. The long-suffering WAR 10 are feeling the brunt of it, and are getting slightly sick of me haunting them round the playground. "Go away, Miss, why do you keep on following us? It's bad enough we have to see you at registration."
Now I'm not starring in the school play, I'm running it. I have a special affection for the backstage crew, walking around in the dark - they're the ones who make it happen. I've lost my desire to take centre stage, and now I sit under it, prompting.
There's a real skill to being involved in the school play. You have to provide chocolate on tap to a whole load of highly strung artistes, you have to provide constant praise, and you have to make them believe that every good idea you ever have really came from them.
I try to remember how I felt that time in school, when in the middle of all the anonymity and noise, I just wanted someone to take notice of me. Christmas makes people forgetful. It's true that school can teach you about everything that you don't want to be, and I want my classes to feel like Mary every day. "We don't care about the spotlight, Miss," say my backstage gang. "It's only there because the darkness lets it."
Gemma Warren teaches at the Latymer School, Edmonton, north London