Abstract
The aim of this paper is to discuss teachers' perceptions of change in their thought and/or practice over time and their
perceptions of what kind of experiences or challenges might have in#uenced those changes. Two mathematics teaching
life histories of Brazilian teachers are examined, considering a context of curriculum development in the state of Sa8o
Paulo, Brazil. Re#ection on teachers' thought and practice and interest in their own development, including interest in
their own learning of mathematics, seemed to be the most important internal aspects in#uencing change and development.
Close support seemed to be the most important external aspect. The retrospective analysis put a good face on
personal change and development. ( 2000 Elsevier Science Ltd. All rights reserved.