Police said a rock narrowly missed the man, who was inside a gym at Kununurra Leisure Centre on Monday night.
It will be alleged several windows were damaged, a defibrillator was stolen and other damage was done to the property.
The trio – aged 10, 11 and 13 – are expected to face Kununurra Children’s Court on April 22.
They face charges of aggravated burglary and commit on a place, stealing, criminal damage or destruction of property, and common assault.
