Our 3 and 5 year old boys love rockets and anything outer space so I made them this NASA Shuttle Orbiting Earth Cake.
The earth cake is made from three layers of 8″ round cakes stacked together and then carved down to a half-sphere shape. My wife and brother-in-law then painstakingly tried to accurately portray landmasses in their proper size and locations (they worked holding a small globe to get it right). It did have the polar ice caps on top using powered sugar, but it disappeared (maybe try coconut instead).
I started the shuttle cake with a piece of cardboard that was cut to the bottom shape of the shuttle and wings. The cardboard was from the box of a toy, not corrugated, and was wrapped in wax paper. I used a 9×13 cake cut long ways, then double stacked to make the body of the shuttle. This was carved to make the general shuttle shape and then lots and lots of stars were added to frost it. We used a Wilton #16 star tip for this and the earth. The back tail fin was also made of cardboard, then frosted.
I used a paper towel tube, cut in half, to make the supports. The back support was glued to the cake board using a hot-glue gun while the front was inserted in earth. The tops were cut on a slight angle for effect. The shuttle was then placed on top and glued to the supports.
The most exciting part was lighting the candles on the rear of the shuttle for the party. Note: put a plate under the candles to catch the dripping wax. The boys loved counting down to blast off!