Other
Color Theory: Lesson Plans
This site was created by an art teacher and has several fun lesson plans that could be adapted to different grade levels. The activities are about color wheels, color theory, tints and shades, and several other subjects.
Other
Color Theory and Mixing: 16 Lessons in Color Theory
Complete site on using color in art. Includes the history of color, psychology of color, color perspective, and how color changes depending on the medium used. Includes activities to help understand how to use color in your art.
Quia
Quia: Color Theory
Four activities quizzing vocabulary terms about the usage of color in art. Matching, concentration, flashcards, and a word search are available. Teachers can use these to supplement their lessons, or to help students review for a test.