In advance: Tint 24 oz. fondant Royal Blue, 16 oz. each Black and Copper (skin tone), 8 oz. Brown/Red-Red combination and 2 oz. each Lemon Yellow/Golden Yellow combination, Orange, Rose, Violet/Rose combination and Leaf Green; reserve 10 oz. White.
Make fondant kids.
To make water slides: Trace patterns from 2007 Pattern Book on cardboard; cut slides and bend to curve slightly. Wrap with foil and ice smooth with blue royal icing; let dry. Roll out white fondant 1/4 in. thick; cut a 1 in. wide strip to fit each slide. Wrap strip around back and fold over edges of slide to make rail; trim off excess.
Ice 2-layer 6, 8 and 10 in. round cakes (3 in. high) smooth in buttercream; cover cake tops with blue-tinted piping gel. Roll out blue fondant 1/8 in. thick; using pattern from Pattern Book, cut wave strips 2 in. and 1 in. high, long enough to wrap around each cake. Attach 2 in. wave to cake with icing; attach 1 in. wave to 2 in. wave with damp brush. Position cakes on Cakes 'N More 3-Tier Party Stand. Cut sign from paper; draw message and border with markers. Tape to 11 3/4 in. lollipop sticks; trim as needed and insert in cake. Position slides and kids.