I have to make a skate board cake . I had a general idea, however I came acorss this one and it was different from the rest. Different b/c it actually was elevated . It looks like there is a cake board the same shape as the skateboard , but i am not sure how they go it to stay up on the wheels . Anyone have any ideas????????????

You are right...all the ones that are elevated seem to have a cakeboard the same shape as the cake (in this case a skateboard).
As for elevating, I would guess that there are supports that are glued (or somehow affixed) to the bottom cake board that are used to provide the structure to elevate the skateboard cake board...the supports are hidden by the donut wheels. Does that make sense?
The wheels aren't really supporting the cake and cakeboard, there are dowel rods (or something of the like) running through the donut wheels that are supporting the skateboard cake.

Hope this helps...

confirming Bunniefluf's take on the cake.

although sketch says car / truck...same principal for skateboard, just different cake board shape

thanks for your imput as soon as I saw the diagram, an idea poped right into my head .

I know exactly how I am going to do it now !

thanks again !