PREPARE cake batter and bake as directed on package for 13x9-inch pan, lining pan with foil sprayed with cooking spray before adding batter. Cool cake in pan 15 min.; invert onto wire rack. Cool completely. Place on platter.
TINT 2 cups COOL WHIP with food coloring; spread onto top and sides of cake. Spoon remaining COOL WHIP into resealable bag. Cut off small piece from 1 bottom corner of bag; use to outline football field on top of cake. Add yard lines with remaining white COOL WHIP.
ADD TEDDY GRAHAMS for the football players and OREO Cookie for the football. Thread marshmallows onto toothpicks; use to make goal posts as shown in photo. Add to top of cake. Keep refrigerated. Remove and discard toothpicks before serving.