I hate sharing my classroom, but we’re so short of space that all ours are constantly in use. Last week, during my PPA time (planning, preparation and assessment), I dashed to the office for tea and a cupcake (which is really just a bun wearing a fascinator) and returned to find my room occupied by the new bloke from maths. He spent the next hour tattooing equations on to my whiteboard with his Kryptonite marker, while his kids ground Quavers into my floor. He finally departed, taking my board wiper hostage, and left me a mug of cold coffee and a book on further maths.

Accommodation is a problem that’s not about to get better. Since the cash for Building Schools for the Future is being thrown at Developing Schools for the Few, it looks like we’ll be in Portakabin shanty towns for some time yet. There is an argument that free schools will relieve the pressure on the state system but this does not bear close examination. It’s like suggesting the new glitzy health spa in town will reduce congestion in the public baths. People join David Lloyd centres so they can avoid swimming next to fat people, Elastoplasts and snot-nosed kids with rickets.

Exclusivity is their attraction. The same is true of free schools: parents don’t set them up as an act of philanthropy; they just want to keep their kids away from everyone else’s verrucas.

The thing that stops me embracing free schools is that they are driven by self - rather than society’s - interest. A couple of weeks ago there was a documentary on the Mayan apocalypse that followed the activities of the religious right in Utah as they prepare for Armageddon. Interestingly, their underground bunkers were small.

It became clear that while they were preaching their end-is-nigh message to the masses, their practical efforts were focused on preserving the chosen few. Their snug asteroid-proof bunkers were just roomy enough for mum, dad, a couple of kids and a cousin once removed. And many free schools look like they will accommodate the same. However much they seem to be offering us a universal message, on 22 December when a suppurating zombie policeman is feasting on your flesh, not a single one of them will open up the door.

Because free schools are often small, if you’re not on their “friends and family” calling circle, you are unlikely to get in. There’s a church-led school in the current round of applications planned for here in the north.

Their USP is their Christian ethos. Now, I have nothing against them spreading the good word, but it would spread even further if they took on an empty business park or a former comprehensive, rather than their preferred former private school site in the Mayfair end of town.

If you swung a cat there, you’d hit four other private schools in the same Latin-conjugating quarter. The free school in question also promises to treat its 700 students (ages 4-18) to the usual challenging curriculum of Classics, MFL and the EBac (English, history and Buying an Aga). It’s heartening that we’re taking benefits off the long-term sick for such a deserving cause.

At least the north has broken its duck. Until now, the new schools have been much further south. Check out the free-schools location spots on the Department for Education’s map: the north looks like a piece of pizza that’s lost its pepperoni while London has all the meat feast on its slice. Still, thanks to Toby Young, “setting up a free school” is the new “garden decking”, so it won’t be long before there’s one in everyone’s backyard.

Anne Thrope (Ms) is a secondary teacher in the north of England.