Costume Box
Have the kids organize elements of costumes so they'll know where everything is when they decide it's time to play dress-up. These elements can come from your own closet or drawers, past Halloween getups and clothes your other children or your kids' playmates have outgrown. Organizing the costumes can turn into a game as they decide which pieces work as hats, shoes, pants, shirts, dresses and accessories.
Who Am I?
Have the kids think of someone-- a cartoon character, historical figure or even a family member--and challenge them to find dress-up elements that will make them look like that person. When they have assembled their costume, have them think of a few clues about who they are and present the clues to the group, which will try to guess who the costume-wearer is. Who Am I gets the creative juices flowing and makes friends laugh in the process.
Trip to the Doctor
Set up a makeshift doctor's office with a waiting room, reception desk to give kids multiple roles in the same game. They also get to flex their creative muscles to invent outlandish maladies and challenge the doctor to find a solution. Button-down shirts can be lab coats, rubber body parts and strangely designed clothing can mask imaginary injuries, and face paint can help create facial changes and cartoon-like wounds.
Dinner Party
Every kid can dress to the nines for this one, whether that means borrowing Mom's old prom dress or Dad's patched-up suit coat. Every attendee can dress in their own style, depending on their definition of formal wear. If the number of kids is small, they can dress up dolls or stuffed animals in clothes that don't fit or are just silly.