Vandals have racked up a repairs bill of more than £750,000 by targeting schools across the north and north-east.
Aberdeen has had the highest number of incidents since 2016, totalling £448,322 worth of damage.
Of the 2,100-plus incidents in the city, St Machar Academy was the most frequently targeted school with 170 reported.
Eleven of those were recorded in December last year alone, when vandals targeted toilets, smashed a plug socket, and even pulled a hand dryer from a wall in a two-week rampage.
Just months before at the school intruders set off a fire extinguisher, broke windows and pulled a heater off a wall between July and August.
By comparison, there were 515 repair jobs across the whole of Aberdeenshire which cost the taxpayer £159,448.
Last night, politicians slammed the culprits for their “senseless actions” and said they were putting pressure on already-tight budgets across the country.
Aberdeen North MP Kirsty Blackman said: “We send our kids to school and expect them to have a good experience, not find vandalism where there should be learning and fun.
“The people responsible for vandalism need to be aware that their actions are not ‘fun’ – they are causing a major impact on our bairns’ education, and could be putting them in danger.”
The P&J figures show that between 2016 and May this year, £67,125 of damage was caused at Moray schools, £81,461 in the Highlands, and £6,283 in Shetland.
Last summer, Moray Council – which is desperately trying to stave off bankruptcy – was hit with a repair bill of more than £10,000 after vandals smashed up the science lab, computers and windows at Forres Academy.
And in the Highlands, a swastika was recently found in the toilets of Millburn Academy while the old Wick High School has been repeatedly targeted.
In November 2016, Markethall Primary School in Turriff was shut for days after vandals broke in and trashed a historic stained glass window, as well as computers and other equipment at a cost of £20,000.
And in April, heartless vandals smashed up the eco-garden at Hill of Banchory for the third time in less than two months.
Back in Aberdeen, vandals targeted six city schools in just one week of August 2017.
Between August 2 and August 9, windows were broken at Cults Primary School, the former Waldorf and at Quarryhill Primary School.
Newly planted trees at Greenbrae Primary School were destroyed and a bin was set alight and graffiti was found at the Holy Family RC School in Summerhill.
Peter Argyle, deputy leader of Aberdeenshire Council, urged the vandals to think about the consequences of their actions.
He said: “Very simply, as a council we do what we can to protect our school buildings, but it is very disappointing that they are targeted in this way.
“Particularly at a time when our budgets are under huge pressure, having to spend almost £160,000 for criminal damage undertaken by whoever it was is ridiculous.
“I think that people who do things like this really need to think about what they’re doing, and the consequences of their actions.”
Education convener Gillian Owen added: “These senseless acts cost residents dearly – not just in terms of money, but impact on school communities.”
A spokeswoman for Moray Council said: “Repairs to schools after acts of vandalism is a waste of taxpayer’s money, which could be better spent on delivery essential services for students.”
And a Highland Council spokeswoman added: “We would urge anyone who witnesses or knows of vandalism being caused to phone the police on 101, or Crimestoppers on 0800 555 111.”