Rocks have been used to smash windows at a school in Altwood Road in Maidenhead.
Three windows in the gym were broken sometime between Saturday and yesterday, a police community messaging alert said.
It did not say which school was targeted.
The alarm code entry system to the building was also smashed, but no-one went inside.Contact 101 or Crimestoppers on 0800 555111 with information.
Top Ten Articles
The victim of an assault in Cippenham was flown to hospital by air ambulance this afternoon.
A rapid response vehicle, an ambulance officer, an air ambulance and an ambulance crew were all called to an address in Earls Lane at 2.10pm.