My 7-year old daughter wanted a mermaid party, so this was the cake I made. I had a lot of fun, and she helped me with it.
I made the cake from a mix, but made my own frosting and colored it with food coloring. I piped the decorations on myself, and added various candies: pretend rocks, sour ribbons for seaweed, gummy fish and octopuses. It was a big hit.