In the paid for version there are families - with these you could (for example) add your three squares into the family and the do things like family.x=family.x+10
you could also give the squares an instance variable (eg ivGroup) and the choose the square by selecting by instance variable and then move all the selected
you could pin objects to another and then when the other object moves so will your squares
also look at containers (stil not sure if they are in free version)