Tux Paint is a simple and entertaining drawing program geared towards young children. It has a simple interface, sound effects, and a cartoon character (Tux, the Linux penguin). Along with drawing brush strokes, lines and shapes, you can also enter text and place "rubber stamp" (or "sticker") images on the picture. Tux Paint is extensible, and could be useful in an educational environment (such as a grammar, elementary, or grade school). It's portable across numerous platforms, and runs well even on slower systems like the Pentium 133MHz.
Shape Collage is an automatic photo collage maker that lets you create picture collages in less than a minute with just a few mouse clicks. Shape Collage creates collages using an intelligent machine learning algorithm that automatically places the photos in the collage and can arrange the photos to form different shapes. You can even save the collage as an Adobe Photoshop PSD file, and edit the collage afterwards in Photoshop or GIMP.