It is not a pretty sight backstage at the Theatre Royal in Drury Lane. Cables, concrete and gloom. But go past the baskets of plastic cabbages (it may be the Teaching Awards tonight, but tomorrow My Fair Lady’s back on stage) and you come to the Green Room.

It is a temporary affair: concrete walls covered with white, filmy fabric, low lighting, champagne on ice and asparagus spears to nibble. This is where the celebs gather. Ralph Fiennes is in the corner in maroon, Joanna Lumley in creamy satin, Royle Family actress Sue Johnston in matt black. But there are teachers too: Mary Pittman, who two years ago picked up the special needs award, and Denise Murray, classroom assistant winner in 2000.

Alistair McGowan arrives with his impressionist partner Ronni Ancona. She taught at Holloway boys’ for four years and tells of taking a group of 40 boys to Paris for five days. “I was determined they were going to do things they’d never done.” They did - they saw the Musee d’Orsay and L’Orangerie.

In glides footballer Sol Campbell; behind him Michael Parkinson who asks for a cup of tea. And so it begins. The chat stops. It’s time to watch the two large TV monitors and Carol Smillie, shimmering in gold velveteen, starts the proceedings. Parky’s feet tap in time to the background music, Joanna Lumley moves nearer a screen.

First up, new teacher of the year Ingrid Spencer. She has, she says, found her place in life through teaching. School leadership winner Rose Marie Pugh says the award “lifts my chin up completely”; ICT winner Keith Phipps says the true winner of his award is his local authority, Birmingham.

Back in the Green Room and Sue Johnston nudges Denise Murray. It is their slot. The actress is about to have a surprise. For 40 years she has been trying to track down her English teacher - a Miss Potter, now Mrs Sutton - who “brought English lit alive for me”. She also cast the young Sue in a school play. “I thought I want to do this, but I don’t know how to. But teachers can see a dream and make it happen - that’s what she did for me.”

Nora Sutton walks on stage. She has long retired, but tells how she too wanted to be an actress. “But I wasn’t as brave as you. I couldn’t audition in front of strangers - and so I became a teacher.”

Barry Cooke is last up to be presented with his lifetime achievement. He says he is determined to stretch his 15 seconds of fame to at least a minute - and does. The head of Hyde technology school (“Happiness Through Success”) retires at Christmas but he is still picked for the school football team. Nowadays, he can choose his position, decide how long he wants to play - and have access to the oxygen from the science department.

And so it is over and there is not a dry eye. Back in the Green Room, there’s the odd crumpled tissue among the canapes.

Then Sue Johnston walks back in hugging her long-lost teacher. But the Teaching Awards are not about celebrities, they are about teachers. No one forgets that. Especially Joanna Lumley. She keeps her poll position by the monitor until the final sound check and the credits roll .

Nothing, she says, is more important than teaching and teachers- “not judges, politicians, sportsmen.Tonight we’re in the presence of real stars”.

Teaching Awards will be broadcast this Sunday on BBC1 at 4.10pm.

Full winners list, Friday magazine