The first incident saw damage caused to metal shed doors with a compost container also emptied at Lincluden Primary School between Thursday 6 April and Tuesday 11 April.
In the second incident at Whitorn Primary School, people tried to set fire to a plastic bench causing minor damage between 12 noon and 3 pm on Sunday, April 9.
A wooden gazebo was also tipped over, with flower pots also smashed, graffiti written on a wall and a window broken in the community centre.
The pirate ship within Penpont Primary School was also damaged sometime between 7.30 pm on Monday, April 3 and 7.30 pm on Tuesday, April 4.
Further vandalism occured at the North West Resource Centre in College Road, Dumfries as the window of an outdoor children’s play house was broken, with offensive comments written on the ground.
Constable Adam Potts from Dumfries Police Office said: “Our enquires at this time suggest children may have been responsible for a number of these acts of vandalism.
“I would appeal to parents to speak to their own children and explain that damaging school property is likely to result in them being visited by the Police.
“Schools have CCTV and we will be reviewing this as part of our investigations. In the meantime I would ask that children stay out of the school grounds during the school holidays.
“Anyone with information about these crimes should contact their local Police Office via 101.”