The patient figure at the back of the class coaching children through maths problems could be any parent helping to relieve the strain on an overburdened school system. Jaroslav Ziga does indeed have children at Zakladni school in the grim Czech town of Usti nad Labem, but he is more than just a community-minded volunteer.
Mr Ziga, a Czech Romany, is a teaching assistant and part of a pioneering scheme aimed at preventing his community from slipping through the educational system into a life of second-class citizenship.
Romany teaching assistants are a rare, but growing, presence in the Czech educational system, which suffers what the United Nations has called "de facto racial segregation". There are practically no Roma teachers in the republic, and most of the country's 50,000 Roma pupils are dumped in what many Czechs refer to as the "gypsy universities", special remedial schools for the mentally retarded. Often this is simply because their first language is a Romany dialect of mixed Czech and Slovak that is unacceptable in the school environment, or because they are deemed hyperactive or otherwise inferior.
Once a child is transferred to a "special school" a return to the mainstream is almost impossible, leaving children condemned forever, and doomed to swell the 80 per cent unemployment rate among Czech Roma or to join the growing number who seek asylum and a new life abroad.
The 20 per cent of Roma students who do make the mainstream often face hostility from non-Roma pupils and a curriculum from which their culture and history are absent. Roma children feel alienated and unwelcome, which further undermines their chance of educational success.
Educational discrimination against Roma children is not confined to the Czech Republic. Save the Children has described it as Europe's worst human rights problem - one third of Europe's three million Roma children never go to school and another third are misplaced in schools for the mentally retarded.
But the scheme that has put Mr Ziga in the classroom is aiming to put this educational apartheid into reverse, building a teaching role for the Roma community, providing positive role models and helping to improve understanding between the communities.
The roots of the Czech project go back to 1993, with the creation of the Premysl Pitter school in Ostrava, an industrial town surrounded by coal mines in the eastern Czech region of Moravia. The school was created specifically to meet the needs of the large local Roma community, whose children mostly went to special schools, and employed its first Romany assistant teacher in September 1993, modelling the post on a bilingual assistant position created in the UK more than a decade ago.
The following year, a Czech non-governmental organisation, Nova skola, became involved, and in 1996 organised the first course for 18 Romany assistants, which gained accreditation from the Czech ministry of education a year later. This recognised for the first time the role of Romany assistants in schools. For the past two years the Czech government has paid the teaching assistants' salaries, a total of around pound;400,000 a year, although most of the funding for training still comes from private sources and the European Union.
There are now 207 Roma teaching assistants working in the Czech Republic, and this year Nova skola provided further training for another 100.
David Murphy is Nova skola's project co-ordinator. A New Yorker married to a Czech woman, he previously spent 10 years working for various non-government organisations in Prague. He has also worked in Croatia, has valuable experience in dealing with minority issues and is an expert fundraiser. He says that while nobody is pretending 300 or so teaching assistants can transform the Czech education system, the mere presence of Roma assistants in the classroom is a breakthrough. "They bring elements of their culture into a learning environment that is otherwise dominated by the majority population. It is often the first time non-Roma children have seen a Romany in a position of authority."
In Zakladni, Mr Ziga is just one of six Romanies working alongside teachers. The school, in a grim industrial town of 110,000 people, 90 miles north of Prague, is working hard to give Roma children the same educational chances as the white population and to break down the kind of prejudices revealed in a recent nationwide survey in which 78 per cent of white children said any contact with Roma was undesirable.
Three years ago Usti nad Labem made headlines across the world when the local white population built a wall that created a ghetto for its large Roma minority, many of whom had moved to the town under communist forced migration policies or, more recently, hoping to find work in the factories. The wall split the school in two, and was widely condemned. It was dismantled after less than a month, but showed the depth of prejudice in the town.
Since the 1989 revolution, which threw out the communists, parents have been able to choose where to send their children to school. This has seen Usti's schools, like others in the country, develop along racial lines as many white parents refuse to consider schools with large numbers of Roma pupils. All but 10 of the 195 children at Zakladni are Roma.
But this desire for separation is not shared by the staff at Zakladni, a well-maintained two-storey building in the heart of Usti.
Iva Santorovka, a white Czech, has been there for 23 years and is aware of the particular challenges in teaching Roma children. "You have to be a friend and mother. For the first month the children are afraid and although they start to relax after that, they still need constant support and affection."
Ms Santorovka says the Roma assistants are like uncles and aunts to the children. "The children tell them far more than they would ever tell me, so they are a useful bridge in the classroom. They work hard and complement the skills teachers bring."
Oldrich Bartak, Zakladni's headteacher, is equally impressed. "This is the era of the Roma teaching assistant," he says. "We have problems with the Roma parents not taking their responsibilities seriously and telling the children there is no point working hard at school. But the teaching assistants give the children something to aspire to."
He wants to see more resources directed towards the assistants' training. "We should concentrate on programmes like this, which assist day-to-day teaching and bring long-term benefits."
And those benefits are not confined to the students. What can be overlooked is the effect the programme has on the assistants themselves.
Jaroslav Ziga was working on a building site until he injured his back three years ago. His wife, Zlata, was already at Zakladni as a teaching assistant and urged him to join her, but he did not find it easy.
"At first the other teachers gave me menial tasks like sharpening the pencils," he says."I think they were just seeing if I was committed. Now we have a good relationship based on mutual respect."
Mr Ziga and his family were recently evicted from their flat by a racist landlord but overall he has noticed a change in the attitudes of both communities.
"Other parents treat me well because I work at the school," he says."My children now play football with white children and that's good, because so many of the problems between the communities come from a lack of understanding. Having more Roma teaching assistants working with white children would help a lot."
David Murphy agrees. As well as increasing the numbers of assistants, and widening the scheme to put Romany assistants into orphanages, Nova skola is keen to provide further assistance to those who have already passed the course. It plans to introduce joint training sessions with the assistants and teachers to encourage teamwork.
"The Roma teaching assistant position should be a starting point," says Mr Murphy. "The long-term plan is to create a system through which assistants can work and study to receive something like a high school diploma either through distance learning or systematic intensive training, then go on to college."
Mr Ziga hopes to combine a four-year teacher-training course with his work at the school.
"I love teaching, it is in my blood now," he says."I want to learn more about it and use it to provide a better life for my family."
Nova skola, email: firstname.lastname@example.org