Most of the life skills a teenager needs are learned at school. Ask any young person the main reason for their coming to school and the reply is rarely one teachers want to hear. Don’t be fooled into thinking it’s anything to do with education, qualifications or preparation for work.

That’s a bonus. It’s all about their friends, stupid. Whether we like it or not, “seeing my mates” is at the heart of the school experience and the most likely answer to the question “what’s the best thing about this school?”

Fortunately, most schools are run by realistic people who have their feet firmly on the ground, or in the case of primary schools, the playground.

The importance of play is hugely evident for small children. But when small children become teenagers everything becomes more complicated and the need for a cooler image takes over. The location tends to shift indoors, where the necessary air of tough sophistication is easier to cultivate.

Most often the school corridors are where the bidding for new friendships, the renewing and reaffirming of allegiances and the sorting out of mini-disputes takes place. It is here that some pretty deep learning goes on - the interplay, the resolution of natural friction, the stemming of emotion, the warmth and joy of “having a laugh”. The corridor is one of the main locations where students learn to cope in and become part of society.

In an ideal world the secondary school corridor would be designed to mirror the town high street: a civilised place to meet, pass the time of day, exchange news, make arrangements while en route to somewhere else. But what if the corridors are built all wrong? What if the architects of a new-build school do not listen to the teachers who know about such things, and the corridors are too narrow, with no natural light and poor ventilation? The high street becomes a back alley, dark and a little dangerous. What happens if it goes wrong before your eyes?

Our brand new school in a deprived and much deserving area of Southampton was finished just over three years ago. It has state-of the art facilities, but it also has a major design fault. We had a vision for our new school; dreams of a happy, civilised, vibrant, environment. In the first few weeks came the crushing reality. The acoustics in the classroom failed every sound test, the floors bubbled up. Worst of all, and apparently unfixable, the corridors were instantly a place of conflict. At lesson changeover, one of our central corridors has to cope with an average of 400 students. It serves eight classrooms and is a main route to other areas. The corridor is 120 metres long, poorly lit and stifling in summer. But worst of all is its width. It is less than two metres across. Go on. Stretch out your arms and add around 10 centimetres. That’s how wide.

There was chaos from day one. Small children were crushed, excitable students shoved and shrieked, teachers became corridor police. Low-level disruption led to wider conflict. Jostling became scrapping. Shouts turned into verbal abuse.

Within the first few weeks the fixers were called in. A quarter of a million pounds was spent on acoustics (it helps if you can make yourself heard in class); floors were flattened at weekends. But how do you fix a corridor?

If the building had been ours, it might have been possible to get a local builder to put in skylights, and open windows at the ends of the corridor to create a through draft, or even knock down a few classroom walls to make it more open plan. But we are locked into a PFI contract.

A recent report by the Commission for Architecture and the Built Environment (Cabe) claimed that many new school buildings were failing to provide suitable learning environments. Our school rated among the worst in Cabe’s audit of 52 new schools built in the past five years. We have been left to pick up the pieces of restrictive building regulations. Teachers are past masters at coming up with imaginative solutions, so we have adapted over time. We release classes at staggered times; we greet students at classroom doors, ushering them in as quickly as possible. We get into the middle of the crowds and cheerfully direct the crush. We have no bells.

In other words, we keep control. But we shouldn’t have to. Schools are perhaps the most critical environments to get right. It’s where it all begins: new social lives, future citizens. Architects need to think long and hard about the immensely important social nature of schooling and give serious consideration to the significance of corridors.

Lindy Barclay is assistant headteacher at Redbridge community school, Southampton