Bowl Cake This half-circle shape, baked in an ovenproof mixing bowl, lends itself to many themes. For a winter party, decorate it to look like an igloo or snowy slope for figures to ski down; for a sports party, turn it into the top of a baseball, basketball, or soccer ball; for an explorer party, create a half globe; for an outdoor party, place figures on a grassy hill.
Square Cake This is the perfect shape to decorate as a wrapped gift, a house, a Lego block, or a treasure map.
Sheet Cake A rectangular cake provides plenty of room for setting a scene: a track or playing field, a quilt with designs in each square, a flag, or a sandy beach.
Cupcakes Top them with designs that echo the theme, or decorate with faces that look like the party guests'. Arrange them to look like a bouquet of flowers or a bunch of balloons with licorice strings.