Anthony Cody is a National Board certified teacher who taught middle school science in Oakland, California for 18 years. He currently works for the Oakland public schools as an instructional coach in science. He also leads professional development for science teachers in his school district. You can read more about his experiences with inquiry and also find science lesson plans (including dry ice) at his web site: http://tlc.ousd.k12.ca.us/~acody/lessons.html