During the Queen's Birthday long weekend, windows in one of the school's toilet blocks were smashed by some form of projectile.

The cost to replace the broken windows so far has reached nearly $4000.

Assistant principal Susanne Wilson said she was incredibly disappointed by the attacks - especially since the school was currently trying to raise $215,000 to complement its Federal funding.

"We've started a major building project worth $5.3million, but our contribution to that has to be $215,000,'' Ms Wilson explained.

"We have to raise that ourselves, and we've just spent under $4000 in repairs.''

Following the attacks, Ms Wilson said the windows would be replaced with stronger polycarbonate panes.

"It's really frustrating.

"That $4000 could have gone into our $215,000, or into our school programs.

"It's really a senseless waste of money.

"I can understand accidents, but this is vandalism - pure and simple vandalism.

"It's becoming an almost weekly event.''

Maffra police Sergeant John Byers said police were investigating the attacks.

"We know they occurred between midday on June 6 and 9am on June 7,'' Sgt Byers said.

Sgt Byers said police believed that the attacks at Maffra Secondary College may be related to another case of vandalism in the town.

"On June 7, the Maffra Beet Museum had four windows broken, and we think the two may possibly be related.''

If anyone has any information regarding the recent vandalism at Maffra Secondary College, they are urged to phone Maffra police on 5147 1026.