What a fun theme for a party - Scooby Doo! For the invites use old comic books or make paper mulch with a blender, old newspapers and flower petals. Add water and mix. Lay it out to dry in a pan over metal grid. Kids will be thrilled when they receive this invitation. You could also add a dog wafer to the envelope. For the party itself, games could include: Pin the Tail on Scrappy, water balloon toss, wash off tattoos, and of course, a Scooby Pinata with Scooby Doo toys inside. A "Mystery Machine" could be created for the cake by stacking several sheet cakes and using legos for the parts like wheels and license plates. The Scooby Doo characters, in miniature toy version, can be placed in the Mystery Machine Cake. What a fun Party for all to attend. Parents could dress up as "the Mummy", Shaggy or other characters to help the kids get in the Scooby Doo Mood. Have Scooby Doo Movies running on every TV to add to the party atmosphere.