It is very important to discipline our kids especially when they are doing things not good. If you caught in the act your children doing things not good, you always to be calm down to say 'No or No way". If it is delicate things, remove it and keep it in the safe place where in you alone knows where it is. Don't ever hurt them. Never spank them regardless of their age. This cannot help them to change their attitude. Let us be the good example for them.