This paper describes a study investigating students’ metacognitive
behavior and abilities in the mathematic class using the open approach. Four 1st
grade students, ages six to seven years, served as a target group from the
primary school having participated since 2006 in the
Teacher Professional Development Project with innovation of lesson study and
open approach. The research was based on Begle’s conceptual framework (1969),
focusing on observing the nature of occurrences in order to describe emerging
facts in the class. In addition, the data were examined by triangulation among
three sources: video recording, field notes, and students’ written works. Data
analysis rested upon 4 open approach-based teaching steps (Inprasitha, 2010).
The study results showed that the open approach-based mathematic class helped
students exhibit metacognitive behavior and abilities relevant to the four
teaching steps: 1) posing open-ended problem, 2) students’ self learning, 3)
whole class discussion and comparison, and 4) summarization through connecting
students’ mathematical ideas emerging in the classroom.