Dress up play is imaginative play. Imagination is the precursor to developing creativity and problem solving. Parents can encourage imaginative play with costumes and props. Children can not hold the imaginary picture in their brain of themselves as a pirate, knight, firefighter or veterinarian in the early years of imaginative play, beginning around age three, and so need 'props' and costumes to help them along. After age seven, children can hold these imaginary pictures of themselves as another character in their mind and no longer need the props as much, but they are still so much fun to have, and kids just bloom in acting when they dress up.