By Tristana Moore
BBC News, Berlin
Teachers claim some schools are turning into ghettos
It is a desperate plea for help. Sixty-eight head teachers have written a letter to the authorities in the German capital complaining about the terrible state of their schools.
The teachers say they are facing worrying levels of violence, poor behaviour and disruption at schools in Berlin, and they claim that some schools are turning into ghettos for children with immigrant backgrounds.
In their letter, the teachers also criticise the authorities for failing to renovate old, dilapidated school buildings.
There has been a huge public outcry because the teachers who complained all work at schools in the heart of Berlin, in the district of Mitte, which is home to the German parliament.
The Gustav-Falke school, a state-run primary school in Berlin, is in urgent need of repair.
In the main hall, a big chunk of the ceiling has water damage and in the staircase, the walls are crumbling.
The school has not been renovated for more than 20 years. The head teacher here is so fed up with conditions at the school that she signed the open letter to the authorities.
The state-run Gustav-Falke primary school is in urgent need of repair
"The last time that the school got a lick of paint was in 1987 and nothing has happened since then," Karin Mueller wrote.
"If I had a flat, I would decorate it every two to five years. Our school is falling apart and it's hardly surprising that parents don't want to send their children here."
Most children at the school come from immigrant families and that poses a big challenge for teachers.
"Eighty-seven per cent of the children have immigrant backgrounds," said Ms Mueller.
"They're Turks, Arabs or Africans and they don't speak German very well. We have classes where there are no German children at all."
At the school, there are posters hanging on the walls advertising German classes for parents.
The head teacher insists that German must be spoken everywhere - but often teachers face an uphill battle.
There used to be 620 pupils at the Gustav-Falke school, but there are now only 360 youngsters because many parents have chosen to send their children to other state schools in different districts.
Those parents who can afford it are sending their children to private schools.
Yvonne Askar sends her son to the Gustav-Falke school, but will soon be sending him elsewhere.
Last year, she pulled out her youngest son, seven-year-old Schadi. His new school is better, even though it involves a long commute.
"We've reached crisis point. The Gustav-Falke School is a disaster," said Ms Askar.
"The plaster is peeling everywhere, the roof is damaged and the toilets stink. Children don't want to go to the toilets because they're disgusting," she said.
"We have far too many children from immigrant families. No-one wants to come to this school, especially native German parents.
"As soon as they set foot here, that's enough to get an impression and they quickly decide to send their children to another school."
End of tether
This is not the first time that teachers in Berlin have condemned falling school standards.
In 2006, teachers at the Ruetli school in Berlin's Neukoelln district wrote to the authorities pleading for the school to be closed.
Berlin teachers have condemned falling school standards before
Back then, the teachers said they would no longer tolerate being insulted and attacked by pupils, some of whom carried knives.
Today, teachers in Berlin are again at the end of their tether.
"Our classes are too big and children are not prepared for school. Some youngsters go to a kindergarten before they come to school, but many don't, so we have to start from the very beginning," said Patricia Thiemig, a teacher who has worked at Gustav-Falke for more than 30 years.
"We have to show children how to hold a pair of scissors, how to use a pencil, and we have to teach them how to speak German.
"The parents don't think school is important and they can't help their children with homework, so our job has become much more difficult. We need more teachers and a social worker in every single class," she added.
The teachers' letter was leaked to the German press and the extent of the crisis in Berlin's education system has triggered a heated debate.
Opposition politicians in the Berlin state government, which is responsible for education, have called on the Senate to invest more in education.
Amid public uproar, the Berlin authorities have invited teachers' representatives to discuss their grievances with the city's Education Senator, Juergen Zoellner. Berlin city officials are adamant that there is extra money earmarked for education.
"The Berlin districts are responsible for the actual school buildings, but we have a programme which provides support to the districts," said Kenneth Frisse, a city spokesman.
"The state of Berlin is going to spend half a billion euros over the next three years on the renovation of school buildings and we also have extra staff to help children from immigrant backgrounds."
However, parents and teachers say the schools are at breaking-point and they are calling for a complete overhaul of the education system.
"The government could do a lot more," said teacher Ms Thiemig.
"Here in Berlin, the German capital, everyone says that education is the most important thing for jobs in the future, but for some reason, the money is going elsewhere, it's being used for other projects," she added.
"It should be used for our main capital, the children, who have a lot of potential."