A three-year-old dressed in a superhero cape collapses in a corner and yells, “I can’t put on my shoes! I can’t!” A four-year-old proudly sets the table “all by myself,” only to fall apart when a glass of water tips over. Preschool children are in the early stages of  developing their self concept — their mental picture of who they are, what they can do, and who they are capable of becoming.