Find out what everyone's thinking in this family-friendly experiment. Come to the Exploratorium on Saturday, June 14, 28 or July 12, from noon-3pm and, using sidewalk chalk, create a giant thought bubble on the museum floor. Anyone can contribute a thought in words, doodles, or pictures.

Ask a question that comes to mind, respond to your neighbor's thoughts, or collaborate with a friend. Help contribute to the invention of -- who knows? For ages 6 and up. Chalk provided.

Thought Graffiti is presented in conjunction with Mind, the major new Exploratorium collection, four years in the making, made possible by the National Science Foundation. It's a place where visitors experience their own thoughts, feelings and actions in provocative and unexpected ways. -- www.exploratorium.edu