Shu-Ling Chang, Fou-Lai Lin22019-08-122019-08-122006-03-??http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/84705This is an interpretive study. The participating teacher “Chin” was a grade 1teacher in a public elementary school in Taipei city. This co-operative interventionresearch lasted for one school year. The researcher played the roles of a facilitator andan investigator. We had weekly meetings to discuss her teaching. Chin progressed tothe top level (Franke et al., 2001). Her action research showed that she had advancedthe cognition levels of students. This paper documents how Chin advanced children’smathematical thinking. We focused on Chin’s strategies of problem posing andteaching.We found that Chin investigated children’s thinking through conjecturing andexperimenting. She posed problems and formed teaching strategies to detect, scaffoldand advance children’s mathematical thinking on the basis of her knowledge ofchildren’s cognition in mathematics. As a result, instructional reform does not succeedwithout sufficient knowledge of children’s mathematics cognition. This studycontributes to the plan of teacher education and reform-oriented teaching.instructional strategiesmathematical thinkingteaching practice