Officers believe a fire was started on the Woodlea Primary School site while no one was there, damaging fencing and the playhouse between 11.30am and 11.55am.
Officers investigating the damage are now keen to speak with anyone who may have seen anything suspicious at this time.
Maybe you saw someone on the school site? Or perhaps you have a dash cam and were driving on Atholl Road as someone entered the grounds?
Anyone with information can call 101, quoting 44200013004. Alternatively, you can call Crimestoppers anonymously on 0800 555 111.