If you know a teacher, or you are a teacher, you’ll understand that many in the profession consider their jobs one of the best in the world, while also acknowledging it can be one of the most stressful.

Teaching in a war zone takes it to another level on both fronts.

But imagine teaching in a war zone in say the London Underground or the Paris or New York metros?

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Well, that’s exactly what is happening in Kharkiv, Ukraine’s second largest city – a city attacked by Russia on a constant basis.

In 2023, the authorities banned children from being taught in regular school buildings here because of the threat they were under from missile strikes.

So Kharkiv city and its education department started working on a plan.

That plan has concluded with the construction of six schools in six metro stations, teaching 4,800 children daily whose families haven’t fled the war.

Intrigued by this new educational experiment, as it’s still considered, we were told to meet at the University metro station in the centre of the city and wait to be taken to the school.

Soviet-era metro stations, and particularly the platforms, are universally grand and ornate, although Ukraine’s are slightly more modest.

Pedestrian walkways though are always crammed with florists, newspaper stands, mobile phone shops and cafes, and Kharkiv’s are no different.

What is different though is that next to the main platform entrance, an adjacent passageway has been sealed off by a white wall with three doors built into it.

We were ushered inside, past a guard and into a concourse with two desks.

In front of us, we could see a wide staircase leading to a long corridor. Above us, large, shiny silver metal tubes stretched into the distance, pumping in air from above ground.

Lining the corridor, we could see a series of white interconnecting cabins, all brightly lit, and from them, we could hear the sounds of children laughing, music, and teachers conducting class in this strange subterranean school.

Perhaps the only school in the world with one corridor.

A door to one of the classes opened, and in pairs, a class of six and seven-year-olds emerged – their teacher at the front and an assistant at the rear.

They’re heading to the bathroom for a toilet break, the staff must keep an eye on them.

If any of the children were to make it out of the school, they could easily get lost in the underground system.

The pupils are spread across seven classrooms with a mix of yellow and green desks and chairs, and walls decorated with bright pictures like rainbows, sunshine and sunflowers, to try to create a cheery atmosphere.

“At first, the children were bewildered by studying here, it felt unfamiliar to them, but interacting with each other and with their teachers helped them to adapt,” Iryna Tarasenko from Kharkiv’s education department told me.

Iryna is showing me around the school. They feel it’s their way of contributing to the war effort.

She said: “In the summer of 2023, the Defence Council didn’t permit children to study in regular school buildings, so, we had to find a solution. This is our frontline – our educational frontline.”

There are of course health concerns for both the teachers and the pupils spending so much time underground, so medical examinations are done on a regular basis.

It is an opportunity for doctors and behavioural specialists to monitor the effects of this war on them.

Dmytro Mitelyov is the neurologist on duty monitoring the children’s behaviour, checking for any signs of stress – physical and mental.

He gently asks each child how they’re feeling, and asks if they have any aches and pains.

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“These are children who haven’t left Kharkiv since the war began, they live in a constant state of stress, multifaceted stress caused by a range of factors. They are exposed to things they see and hear, like alarms, explosions, and they feel it all,” Dmytro told me.

“When these children grow older, all the trauma they’ve endured during their formative years can, unfortunately, leave a lasting and serious imprint on their mental health. They haven’t had a healthy, carefree childhood – the kind where they can learn, play, and feel safe as children normally would.”

As the first group’s school day ends, children from one of Kharkiv’s most bombed districts, wrap up warm before being led to the surface to catch a school bus to their old school – which was hit by a missile.

It’s still where they meet their parents for normal pick-up.

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We jump on the bus with them for the journey past destroyed government buildings, shopping centres and restaurants.

When the air raid suddenly sounds, I look around to see how the children and teachers on this bus will react.

They barely flinch it’s so common.

“People have, to some extent, adapted,” one of the headmistresses, Olena Nikolienko, said.

“If we see missiles coming, heaven forbid, we’ll stop near a designated shelter, following our evacuation plan, and that’s where the children will go for cover.”

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Remember, these children are safe underground at school, up here they are not.

During the bus ride, 10-year-old Alisa began quietly sobbing. Her teacher told me her grandfather was killed four months ago on the frontline, and since then she has been prone to tears.

Alisa’s teacher comforted her and told her everything would be ok.

It feels like everyone here has to carry their own sadness.

Everyone.

Parents, standing in the first snowfall of the season, greet the children as they get off the bus.

The kids run off the bus, and start throwing snowballs at each other, enjoying this precious moment.

It will be the last time they’re outside today.