When I was working on an article a few months ago, I came across a idea that I would like to start as a fun tradition with my kids. When the birthday kid has gone to bed the night before the big day, I am going to sneak into the room and decorate it. One of the ideas that I came across was making a happy birthday sign to hang on the wall and have the rest of the family write a note to the birthday kid on the note. I also liked the idea of blowing up balloons and put the balloons in the room. I think that my daughter would really like it if I also make a magic curtain door out of crepe paper.
My son has a birthday this summer and I think I am going to try this out. I'll let you know how it goes.