As long as there has been a mouse connected to a computer there have been tools for making drawings on a computer. Here are five drawing tools that you might consider the next time you or your students need a free and easy drawing tool.
Sketchpad : http://mugtug.com/sketchpad/
Art Pad : http://artpad.art.com/artpad/painter/
Graffiti Creator : http://graffiticreator.net/
Bomomo : http://bomomo.com/
Crayola's online drawing canvas : http://goo.gl/Iognx
Odosketch : http://sketch.odopod.com/
Draw It Live : http://www.drawitlive.com/
Coloring 4 All : http://www.coloring4all.com/
Draw Island : http://drawisland.com/
FlockDraw : http://flockdraw.com/
Sketch Pad : http://www.onlinesketchpad.com/