If you are looking to boost student creativity through art (without the mess!) try using The Art Zone from the National Gallery of Art.
The NGAkids Art Zone offers an array of fun online art activities. Interactives such as Photo Op, Dutch Dollhouse, Jungle, and Collage Machine encourage compositional experimentation and a vivid understanding of collage and photomontage techniques. BRUSHSter and PaintBox are painting tools that encourage free expression and visual experimentation. SwatchBox is a tool for mixing and drawing with millions of colors. Pixelface is a hands-on virtual portrait activity. FACES & PLACES helps you create portraits and landscape paintings in the style of American artists. STILL LIFE lets you create interactive art that mirrors the paintings of the old masters. SEA-SAWS has photographs of natural and man-made objects that can be arranged to create a seascape or an abstract composition. The BUILD tool helps you construct animated characters and set them in motion. Additional activities include 3-D Twirler, Mobiles, Cubits, Diamonds, and more!
Children of all ages (and even adults!) will enjoy experimenting with art while playing with the activities on this site. (Art Zone interactives require Adobe Shockwave player.) http://www.nga.gov/kids/zone