First, they can structure the environment to prevent conflict from occurring in the first place. Toddlers have such limited skills. Its better, for example, to buy two or three of the same toy rather than buying several different toys. That way, toddlers won't have to wait long for a turn with an attractive toy. It also helps to divide toys up between the children before they begin to play.
Toddlers have a great deal of difficulty sharing materials from a common pile.
Give each child his or her own pile. Make it clear that this pile belongs to Jimmy and that pile belongs to Terry. This will help you avoid arguments. Many conflicts can also be avoided by limiting the number of children playing in any one area. Fewer children make for fewer social problems and, thus, fewer conflicts.