This book describes and traces efforts to change teaching practice in response to current national reforms in mathematics education. It explores changing practice from the vantages of both teacher and researcher. Chapters include: (1) "Do You See Any Patterns?"; (2) "Learning to Comprehend Mathematical Ideas in Topics, Texts, Tasks, and Talk"; (3) "The Teaching Has Been Missing"; (4) "Learning to Appreciate Teaching as an Improvisational Activity"; (5) "Bendable Rulers and Other Moments of Improvisation"; (6) "Learning to Share the Dance with Students"; (7 "What Should I Do Next?"; (8) "Learning to See Knowledge Differently"; and (9) "Learning to Teach While Inventing a Practice". (Contains 135 references and an index.) (ASK)