The cake for the mothers' group birthday party

It has become traditional for me to make the mothers' group birthday picnic cake. Here they are in order:

The first year was a cupcake tower (2005):









The second year (2006) was a number 2 cake with animal candles:

Then a number 3 with smarties (2007):








A number 4 with racecars driving through fields of flowers (2008):

And this year (2009), a number 5 with a rainbow: