NAEA's Lesson Plans - This subset of the NAEA website contains lesson plan starters for art projects.
Kinder Art - Ideas, lessons plans and more by topic.
Educator's Reference Desk: Arts Lesson plans for the visual arts from the Educator's Reference Desk.
Artlynx International: Theatre Resources - Resources by topic.
ArtsEdge lesson plans - From the Kennedy Center. Use the drop down menus on the left to narrow to specific subjects and grade levels.
Folger Shakespeare Library - If you're teaching Shakespeare's works, you've hit the lesson plan jackpot at the Folger Library. Find primary resources and classroom ideas, organized by title.