This year's summer reading program (SRP) theme was "Make a Splash: READ!" so I did a bulletin board of a mermaid sitting on a rock in the ocean. The kids who signed up for the SRP were able to color a sea creature and write their name on them. Then I stapled them to the bulletin board. It was very cute, in my unbiased opinion.
I wish I had taken a picture of the whole board, so you could see it, but I don't think I did. Here is a picture of the centerpiece, a mermaid that I traced using the template in Projection Art for Kids, which I borrowed through ILL:
I didn't like the way the tail was drawn in the original picture, so I redrew it for my bulletin board. It is one of my favorite parts of this mermaid.
By the way, Projection Art for Kids is a great book for if you want to paint your own murals in your kids' rooms. You could also use it in any setting where kids will be (dentist's office, doctor's office, daycare, library, school, etc.) The book says kids can do it themselves, but I would not recommend it. Some of the projects might be simple enough for older kids though. You can use an overheard projector and transparencies or borrow an artist's projector (you can also buy these for about $50-100 online.)
I also made a box for the middle schoolers to put their drawing slips for their prize (a gift certificate to the local movie theater). The supplies were purchases from Oriental Trading (the High Seas Kit):
Oriental Trading has cute papers, but I don't like cutting them on the Cricut and prefer them for projects like this, where I am just throwing something together. It was nice to have a decorated box. The middle schoolers really noticed it, and yet it didn't look too babyish.