This is a challenge to any dog, particularly a collie. Children make high-pitched noises and sudden movements which can trigger collies. The dog must not be allowed to run up and down with children. It will get more and more excited and start jumping up and pulling at clothes or try to herd the children by nipping. A collie must be kept occupied or it will go self-employed.
Indoor kennels are great to give the dog a safe den.
Leave it something it can chew and remove the toy when the dog has something else to do. Their toys are your toys. Retain at the end of the game. Collies like to be part of the team and crave companionship of humans. Don't let the dog follow you from room to room, it should spend some time in it's bed alone when you are in.