They say that the human body can't recall pain, if it did no woman would have more than one child and the human race would die out. I believe the same principle applies to school shows.
School shows should carry a health warning, they can seriously damage your sanity, your social life, they lead to sleep deprivation and bouts of intense paranoia. Once they are over, though, the elation (or is it relief?) is incredible. Somehow at the last minute some miracle happens and it all comes together, well that's the theory at least.
For a first production as an NQT, I would be modest in your ambitions, especially if you are going to be director, choreographer, producer, lighting designer, stage manager and general ogre all by yourself. Choose your show carefully: Starlight Express in the school hall is likely to present some technical challenges and Year 7 students are bound to struggle with Moliere in the original. Go for something you think the pupils (your cast, your company) are going to enjoy.
Shows can be the making of some young people. You may find that obnoxious Johnny Herbert has a talent that would give Topol a run for his money and if you're the one who brings it to the fore your life may change dramatically for the better. They give pupils a tremendous sense of self worth and confidence and, despite all the stress, they are fun. You do need to choose your pupils carefully: one Johnny Herbert is an achievement, 30 of them in the darkened wings with 200 parents 10 feet away is a recipe for, well, I'll leave that for your worst nightmares. You need to know that the pupils will turn up for rehearsal (a slip to this effect, signed by parents can be very useful) and that you can control them when they do.
Sort out the dates of your performance before you start, there's no point spending months on this project only to find that the local rotary club is holding a Hawaiian night and you can't have the hall.
Plan rehearsals carefully, you don't necessarily need the whole cast there for all of them and, let's face it, watching other people stumble over their lines when they could be watching Neighbours is boring and likely to de-motivate the kids. That you don't need. It's very helpful if you can find someone else to help with the practices: they can operate the keyboardstape recorder etc while you concentrate with what's going on stage.
Sort out what you need as early as you can, this will give you plenty of time to twist the collective arms of the art and music departments for the scenery and music, cajole home economics for the costumes and interval refreshments, and bribe the rest of the staff with promises of post-production drinks if they'll help with anything else.
You will also need to sort out a programme. Entrust this to some of the pupils, one who can spell to get the names of the cast, one who can draw to design the front cover and one with a winning smile to persuade the reprographics technician to print the thing.
On the night you will need someone to sell programmes and any on-the-door tickets and possibly some pupils to show the audience to their seats. Tea and squash pourers will keep them happy in the interval. The school may also like to have people "on security" to make sure there are no unwelcome intrusions.
In terms of backstage help you will want in the wings a prompter and a couple of Shh-ers. You may also want to have some staff to supervise pupils who are not on stage. Someone (probably more than one person) will have the joy of slapping on the greasepaint, in my experience one teacher who has a vague idea of what needs to be done (easily gleaned from a glance through a book) and a few enthusiastic pupils will suffice.
Sooner than you know the day of judgement will be upon you. Panic, run round like a headless chicken, try not to scream when the lighting lad puts a foot through the most prized piece of scenery, then enjoy the applause, the smiles on the pupils' faces as their heads swell so much they can hardly get out of the school - and get your wallet ready to repay all those favours!