Imagine a school where attendance is voluntary, there are no timetables and you can even take your bed into the classroom.

It may sound incredible, but this is an everyday reality for children attending the Oxfordshire Hospital School.

One of only 30 hospital schools in the country, Oxfordshire's school teaches patients at Banbury's Horton Hospital, the Highfield Adolescent Unit and Oxford's new Children's Hospital, where I have come to meet head of department Margot Shawyer.

Mrs Shawyer explained: "We are both like and unlike any other school. Whereas children attending a mainstream school will have lessons in an allotted time and may work to a curriculum each day, the children who attend the hospital school all have very individual needs and we tailor their education to meet those needs.

"Some of our pupils may be undergoing chemotherapy, or have had major surgery, or are even just coming in for a day.

"So, we start each day by assessing which children are in need of teaching, what kind of teaching they need and going from there, but even then our planning can change throughout the day.

"We work around treatment sessions, how young people are feeling on any given day and even just visitors turning up who may have come a long way.

"It can be a little frustrating, but flexibility is the key to teaching here - you cannot be a controlling teacher in this environment!"

Mrs Shawyer admits some children are surprised they'll be able to continue with their schoolwork in hospital, but said most are enthusiastic pupils.

"Schoolwork can be reassuringly familiar in the hospital environment and artwork in particular is a very successful way of engaging pupils who may be going through difficult or painful procedures."

Every patient is a potential pupil. Unless they are too unwell, they all have the opportunity to take part in appropriate schoolwork and that can mean lessons by the patient's bed, in one of the school's classrooms or a combination of both.

Mrs Shawyer said: "We do have young patients who are unable to leave their bed and therefore bring their bed into the classroom."

Just as each child in the hospital is treated individually, a lot of the teaching is one-to-one. The school does have its own curriculum, but there is no regular timetable: Flexibility, again, is key.

Mrs Shawyer said: "We ask children for their input when deciding what lessons they need.

"For example, they might be learning about the Greeks at school and want us to continue with this.

"Others want to do artwork, and we might offer them help with something they are struggling to understand at school.

"Very often it is strange for a child initially to have a teacher all to themselves.

"They are usually part of a class and find 40 minutes of one-to-one teaching unusual, but most really enjoy it and we have great results.

"On occasions we have even been able to detect glitches in educational needs that a school may not yet be aware of and alert them to that.

"But first and foremost we are a school, we are here to teach and the children to learn, it's just the way we operate that makes us a 'special school'."

The Oxfordshire Children's Hospital teaching unit has four teachers (one part-time and two teaching assistants) and whereas tuition was once given across Oxford's hospital sites - the JR, the Nuffield and the Radcliffe Infirmary - it is now centred around modern and light school rooms, an IT room and a school office - all situated on the upper floors of the new Children's Hospital.

Young people themselves have also given their input into the running of the school via the feedback group at the Children's Hospital in Oxford, the Young Peoples Executive (Yippee). Suggestions so far include introducing more flexi-time to the teaching day, with a later finish than 3.30pm.

Ellie Fear, 14, from near Thame, is a member of Yippee and regular pupil of the Oxford Hospital School.

She said: "I have been in and out of hospital since I was a baby so I have had quite a lot of experience of the hospital school.

"It can be worrying to know you are missing so much school and you are getting behind, so the hospital school can be a real help."

Ellie has fluid on her brain and this means she and her family never know when she will have to come back into hospital or how long for.

She said: "One of the teachers here has just contacted my school about having some work sent in.

"It can really help to have work to do. Just talking about it has made me want to work on a picture I have been drawing."

As well as one-to-one and classroom teaching, staff encourage group work involving music and art and there are regular visits from musicians, artists and the museum service.

Amie Ing, 11, from near Thame, has bone cancer and her family has spent most of this year coming back and forth to the JR. The hospital school has been a welcome break from her gruelling treatment.

She said: "I really like the hospital school, especially design and technology. I have spent my last three sessions making a garden from different materials including The Oxford Times newspaper.

"I will be here all next week too and I'm looking forward to what I will be learning and making."

Amie's mum Sandra Ing, 40, said: "Amie loves the school here. We have only had four weeks at home since January and Amie is going through so much, including chemotherapy and radiotherapy so her schoolwork is a welcome distraction for her."

The school is funded by Oxfordshire County Council. The Oxford Radcliffe Hospital Trust has provided facilities for the OCC to rent on the school's behalf and charitable funding has helped sponsor the school areas in the building of the children's hospital.

Margot Shawyer said: "Being a hospital school teacher can be very challenging - there can be very good but also difficult times, but it is a very rewarding job.

"I see some young people who come here as babies and grow up attending our school.

"Some leave after just a day or two, but all learn from us, and it is a privilege to know you have helped them along their way."