Spring Lane Primary School in Spring Boroughs had to replace every item in the classroom, as it had been contaminated with asbestos.
The damage – which amounted to £7,844 – was caused by David Bush, of Stanley Street, Semilong, after he hotwired t
he truck and ploughed it into the primary school.
Bush, aged 21, was convicted of unlawfully taking the truck and damaging the school at a trial at Northampton Magistrates' Court yesterday.
Abigail Turner, prosecuting, told magistrates Bush had taken the truck, which was being used to carry out building work at the school, at about 11am on Saturday, March 10.
She said: "The headteacher was working inside the premises when he heard a loud bang. He thought it was workmen at the school, as building work was taking place at the school at the time."
When Duncan McAlpine, the headteacher, went to investigate the noise he saw a "gaping hole" in one of the classrooms.
The court heard that, as a result of the damage, the classroom was contaminated with asbestos, as the truck had smashed through asbestos insulation board, spreading deadly fibres across the room.
A teacher, who lost 20 years of work in the classroom, broke down in tears when she heard everything in the room had to be thrown away.
During the trial Bush admitted driving the truck, but denied causing the damage. He told magistrates that after hotwiring the vehicle another man drove it into the building. The 21-year-old claimed he then jumped on the truck to reverse it out of the classroom.
However, magistrates said they did not believe his version of events, as he had claimed in an earlier police interview that he had no idea how the damage had been caused.
Finding him guilty, presiding magistrate Patrick Flemming said: "We know you committed the offence recklessly and you caused serious damage to school buildings." Bush will be sentenced next month.
