Rachel Wing DiMatteoRachel Wing DiMatteo is a coauthor of Fostering Geometric Thinking (2007) and its professional development companion, The Fostering Geometric Thinking Toolkit (2008), both published by Heinemann.Shestudied the development of mathematical knowledge whle pursuing her Ph.D. in Psychology (cognitive development). Since then Rachel has been involved in the creation of professional development materials that help teachers understand the development of mathematical knowledge in their students. Read More Read Less