Through quantitative video analysis of four algebra classes and statistical analysis of various types of teacher evaluation behavior in the classroom teaching, we get: (1) Teacher evaluation behavior in classroom is close to take 1/5 of the total time of the classroom teaching, and it appears most frequently in class exercises and take the longest time; (2) There are many forms of teacher evaluation behavior in classroom, and most of the behaviors are positive assessment; (3) Recognition evaluation is relatively conservative in a single form without losing fairness; (4) Classroom assessments of teachers' behaviors are primarily concerned about students' knowledge and skills mastery, and it is less involved in student feelings, attitudes and behaviors; (5) The correct teacher evaluation behavior in classroom will inspire students to create internal motivations; and (6) The correct teacher evaluation behavior in classroom can stimulate the potential of students.

While many studies on early algebra have been conducted, there have been only a few studies on the operation sense as the fundamental element of algebraic thinking, especially the fraction operation sense. This study explored the dimensions of fraction operation sense and then investigated students' fraction operation sense. A total of 183 of sixth graders were surveyed and 5 students who showed high operation sense were clinically interviewed in order to analyze their algebraic thinking in detail. The results showed that students had a tendency to use direct calculation or employ inappropriate operation sense rather than to use the structure of operation or the relation between operations on the basis of algebraic thinking. This study implies that explicit instruction on early algebra is necessary from the elementary school years.

The purpose of this study is to investigate the relationship between creativity development and debate in solving a probability task. We developed the probability task with instructional strategies facilitating debating among students. 33 students in grade 11 who were identified as gifted participated in this study. The findings indicated that debating leads students to critical and reflective thinking on prior learning regarding probability concepts, which nurtured creative ideas on sample space.

The Korean mathematical curriculum has been changed three times during the resent five years. It led to changes in textbook system. In the 2007 revised mathematics curriculum, workbook was developed focusing on student's self-oriented learning, effective practice in differentiated classroom, and mathematics problem solving considering individual difference. This paper examines the characteristics of the tasks and the way the tasks are organized in the textbooks and the workbook in accordance with the 2007 revised mathematics curriculum; comparing with the function section before and after the amendment. Researchers examine whether the textbook and workbook were accomplished the purpose with "cognitive expectation", "level of cognitive demand", "and "response types". Researchers revised framework of [Son, J. W. & Senk, S. (2010). How reform curricula in the USA and Korea present multiplication and division of fraction. Educ. Stud. Math 74(2), 117-142] to make them suitable for the function section at the seventh grade.

These days, with the emphasis on statistical literacy, the importance of communication is the focus of attention. Communication about statistics is important since it is a way of describing the understanding of concepts and the interpretation of data. However, students usually have trouble with expressing what they understand, especially through writing. In this paper, we examined preservice teachers' difficulties when they wrote about statistical concepts. By comparing preservice teachers' written responses and interview transcripts of the variance concept task, we could find the missing information in their written language compared to their verbal language. From the results, we found that preservice teachers had difficulty in connecting terms contextually and conceptually, presenting various factors of the concepts that they considered, and presenting the problem solving strategies that they used.