1. Start with a 9" X 13" sheet cake. It can be chocolate or yellow cake -- whatever your family prefers.
2. Cut a 2" x 3" rectangle from the upper left corner. (This piece will not be used, so freeze it for later or eat it quickly while no one is looking).
3. Round edges along top of the cake.
4. Mix 1 cup vanilla frosting with yellow and red food coloring to make a classic school bus color. Frost the surface and sides of the cake with the bright yellow-orange.
5. For the windows, mix 1/3 cup of vanilla frosting with blue food coloring. Create one large window (for the driver), four smaller ones (for the students), and a headlight.
6. Use 1/2 cup of chocolate icing to frost the bottom of the bus. Place the remaining frosting in a zip-top bag. Snip off a small corner piece and pipe the name of your child's school 1 inch below the windows. Save the extra frosting to outline or create any other details.
7. Stop sign: Cut a red fruit leather snack into a hexagon and place under the driver's window. Write "STOP" with frosting.
8. Tires: Divide a chocolate-covered doughnut in half horizontally and press the cut-sides down into the cake.
9. People: Draw hair and faces on candy wafers (or other round candies of your child's choice) with chocolate frosting to create students and driver. Roll out a gumdrop and cut lengthwise to create the driver's body, and add a cap made of candy or frosting.