Yvonne Hill leads a school with about 140 children and a staff of just under 30 - so few leadership problems there, you might think. However, the school has several sites, caters for youngsters aged two to 19,whose needs are as varied as the countries they come from. And while the teacherpupil ratio is one to five (and often one to one) , numbers fluctuate from day to day, and even hour to hour.
Ms Hill is the headteacher of Great Ormond Street Children's Hospital School. She says her job is the most satisfying imaginable, but also that the task of managing the teaching of seriously ill children is extraordinarily complicated, and about to become even more so. Great Ormond Street is a tertiary referring hospital which means it only accepts patients referred by other hospitals throughout the UK and across the world.
Pupil and staff numbers have increased steadily since the school was opened in 1951 with a single teacher working out of one classroom, but this year the biggest expansion so far looms. Between now and early January pupil numbers are rising to about 170 and staff numbers to 33, of whom 23 will be qualified teachers.
Children will be taught in seven hospital buildings in the central London complex - including Great Ormond Street, University College London Hospital, the National Hospital for Neurology and Neurosurgery and the Patient Hotel. Lessons take place in schoolrooms, smaller ward teaching areas, specialist units, such as transplant suites, and beside the child's bed.
Until now Ms Hill has juggled all the management balls herself - with the help of a deputy and a three-teacher management team. But this greater workload has meant a different way of thinking.
"We have to embrace a more formal way of doing things, but I want to ensure that this will not ruin the staff's informal spirit of warmth and friendliness," she says.
"Some of our old customs will probably have to go. Because teachers will now be working out of different buildings instead of our main schoolroom, my enormous, well-thumbed diary full of teachers' pencilled notes detailing daily changes caused by the health of individual children may have to go in favour of a more impersonal online version.
"That means I will lose that moment of personal contact as teachers pop in to bring the diary up to date. That makes me even more determined to keep our sacrosanct twice-weekly senior teachers' get togethers - the bacon, lettuce and tomato sandwich on a Tuesday and the quicker Pep (personal education plans) lunch on a Friday.
"A recent meeting looked at the problems of teaching children in the department of psychological medicine. We are not trained in this field so it's good for the children to realise that while our teachers do their best to understand their needs, they themselves have to adapt to our world because they won't always be with experts."
The increasing number of pupils, staff and teaching areas, led to the setting up of a leadership management team earlier this year.
The team decided to decentralise the headteacher's heavy workload by dividing the teaching sites into three more or less equal sectors with an experienced teacher in charge of each one. Ms Hill feels that her hard-working team should be given the recognition they deserve and has made each sector head an assistant head. She will now focus on the overall management of the extended school.
Walking around the teaching sites in the different hospital buildings with Carole Flynn, one of the new assistant heads, shows immediately why the school's teachingpupil ratio cannot be tampered with.
One-to-one bedside teaching is not just a matter of tutoring. The daily fluctuations in a child's state of health - as revealed by talking to their doctors and nurses - determines the teacher's choice of lesson for that day.
During our marathon walk around we visited the dialysis unit where children are taught while undergoing treatment for kidney problems. These lessons often consist of helping them with work given them by their home school.
Teachers also chat to the parents or relatives who sometimes keep the young patients company as was the case with one small, blind and autistic boy.
The chat can help both relative and teacher.
Children who feel well enough come to the classrooms where a foundation curriculum is taught and translation help given for those who speak little or no English.
"We aim to provide an enriching and enjoyable teaching experience for our pupils which ensures a link up with normality," Ms Hill says. "When they are in the classroom they are treated like pupils not patients and we do not inquire what is wrong with them unless we need to know. Because many of our pupils cannot go out into the world, we do our best to bring the world to them.
"Recruiting the right teachers is the school's top priority. Advertising brings in a very good response, often from those in either primary or secondary mainstream teaching, but some candidates who believe they would love teaching here get upset when actually visiting the school, and realise the job is not for them.
"The relationship between teachers and pupils is extraordinarily close and because of the nature of pupils' illnesses, bereavement therapy is available for all members of staff.
"Advertising for specific subject teachers does not necessarily bring in the right people. The priority is to take on people who are positive, enthusiastic and able to empathise with sick children and with the existing teaching team - and then they need to be well qualified in their subject and also ready to teach other subjects when needed.
"We work an extended school year to allow children access to education whenever they are in hospital."
The original 1951 classroom lives on as the school's main base. Ms Hill says that its lack of space is her biggest problem.
"We continue to adapt it because we have to, but it is not easy," Ms Flynn says. "We never turn a child away who is spending more than two weeks in hospital or is returning regularly for treatment. In addition, siblings of pupils and those patients under five who are deprived of home schooling are welcomed in. Sometimes children and parents just arrive on our doorstep and ask to join in."
Schoolroom areas, bar the toilet, are multi-purpose and hot-desking is the norm. Keeping every bit of the open-plan 150 sq-metre space tidy is a must if the system is to work.
Ms Hill admits that she resorts to bribing staff with the promise of daily mugs of quality coffee in return for continuous tidying up. Classroom activities take place at one end while the other is used as a senior school teaching area cum school library cum dance and music area cum conference space for students, teachers and the all-important meetings with nursing sisters and the school's committed team of governors.
Off to one side are a couple of admin offices and on the other is a small outdoor teaching area and playground with colourful railings designed by the smaller children and a shed where everything that does not fit elsewhere is crammed in.
Lastly, the kitchen doubles as the staffroom, with staff notices stuck up near the kettle, and a food technology teaching area. "We squeeze in up to 30 pupils, although how we manage to fit in their wheelchairs, drips and other apparatus is beyond me," Ms Flynn says.