This is a cake I made for my son, who was 4 years old at the time. He absolutely loved Blue's Clues.
To make this cake I used one 8-inch layer (flavor is your choice, I used chocolate) and the rest I made into cupcakes. I used 4 cupcakes for the pawprint toes.
The frosting was a simple buttercream frosting, I colored most of it "blue's clues blue" and left the rest white for the trim. Four years old is the perfect age, as I put one blue candle in each pawprint "toe."