I grew up in a home where good manners were encouraged all the time; so even now in my family no one is allowed to move from the table until we're all almost about done if not done yet. Same rules applies in daycare, I have set up two trays with the craft of the day and the early lunch finishers can start working on that, while the others finish, when the other ones see what's in the tray to do then they finish their lunch asap.