For my daughters 3rd birthday we decided to go with a blue's clues theme party. The invitations were made of construction paper and on the inside of the paw print we had the friends name and on each of the toes we had the time, place and special message. We decided to go all out and wanted to spend as little money as possible so we made most of the decorations and just bought balloons and streamer.(blue of course) There were paw prints leading to the front door and one on the window leading in.  As the guest arrived we had mailbox by the door and the kids had to put their cards inside him. He was just made out of a box with construction paper.  We gave him a face and a flag and he was adorable.  We made ALL the Blue's caricatures out of construction paper and sticky tacked them to the wall so they wouldn't leave marks.  Each caricature was about 1 foot to 2 feet high and were a real kick with the kids.  The caricatures all had presents made of construction paper too and to give them dimension real gift bows. They also wore party hats. I had a chair just like Steve's that I want to re-cover but ideally it is a dark red and became the thinking chair. Behind the chair I had Tickety made from construction paper.  I also had the felt people, I made them out of felt, used a black PC. of felt for the background and put glued it into an old picture frame. The kids were allowed to play with them and change their poses. For games we played pin the nose on blue, musical paws and the hunt for Blue's clue.  The game, paws, and note books were also all made of construction paper. Cheap but cute.  The cake was of Blue' face. I used a circle pan for the face and a heart cut in half to form each ear. I used white icing for the eyes and put a brown smartie in each. We served blue Kool-Aid and for people who didn't want it we served blue ice cubes.  I served all the chips and dip in different sized and colors of buckets and just glued eyes and mouths to their fronts.  I also made a big paw out of blue Jell-O.(big hit)  The sandwiches were cut out to look like dog bones. I just used two colors of blue plates, cups, and napkins.  The kids had a great time!! It was a lot of work, but tons of fun.