Spray paint has to be one of the most fun techniques in making art. Without the use of a brush, there is much more freedom for the artist, and children love how quickly the paint leaves the bottle. For the artist holding the spray paint can/bottle, there is an element of surprise for where the paint will fall and how much will come out.
For this activity I used water squirt bottles rather than compressed air paint cans, and let the children choose a few colors to mix and fill them with. Using the spray bottles teaches the children about their small motor-skills and control of the muscles in their hands. Depending on how hard they squeeze, the amount of paint that sprays out is effected. They also could move about and pick different distances to spray from, which also effected the amount of paint touching the paper and the consistency of it.
They had lots of fun posing for the silly pictures we used for stencils, cutting the stencils and then spray painting them. When the paint dried we pulled off the stencils and tried to identify each person by the outline of their figure left in the paint.