My 4 year old wants an airplane birthday party for his fifth birthday which is May 28, so after pondering over this I have decided to rent a Moonwalk, So they can jump high into the sky!!! Hang airplanes from our outside arbor and give gifts pertaining to airplanes.  I will make our own invitations as well as the gift bags with the same logo which will be some sort of airplane. Since I have a few months until the big day I am even going to attempt to make an airplane cake!!!! Hope this helps someone out...If anyone has any other ideas please share them with me. Thanks Susie