Thousands of pounds worth of model railway exhibits have been destroyed in an act of "total wanton destruction".
Market Deeping Model Railway Club lost years of work in the raid at Welland Academy in Stamford on Saturday.
Its chairman Peter Davies, 70, said exhibits were smashed, thrown around and stamped on, including a locomotive unit worth about £8,500.
Four youths have been arrested on suspicion of burglary and criminal damage.
A funding page set up to raise £500 for the club has made more than £32,000 in a matter of hours.
One contributor, Barry Cave, posted on the page: "Horrendous act of vandalism, hope my donation helps a little."
The club had set up the exhibition in the school for viewing on Sunday.
Mr Davies, who trained as a teacher and youth worker, said he was in "total confusion" over the vandalism.
"Models that were made over years were trodden on and thrown around. It's a total wanton destruction of the highest order.
"I've never experienced anything like it. A hurricane would have done less damage."
Mr Davies said club members were "devastated and distraught".
"Can you imagine your life's work wrecked?" he said.
"One guy spent 25 years on his work and it's wrecked, it's just horrendous.
"We will never have the time to build the sort of layouts again, that's where the anger comes from."
He said the club had received support from "all over the world - as far away as New Zealand".
He added: "We will rise from this, no question, we will be bigger and better. But we'll never get the years back it took to build those exhibits."
Lincolnshire Police said: "On arrival at the school we arrested four youths, who were on the premises, for burglary and criminal damage.
"We are continuing our investigation and confirm damage was done to model railway exhibits which had been set up in the school for a display today [Sunday]."
The youths were released on Saturday evening on conditional bail pending further inquiries.