The purpose of this study was to examine the effects of co-teaching on third-grade elementary
school students\' academic achievement, class preference, and class participation in Korean language.
For this, S elementary school\'s two classes composed of students(i.e., 32 students without disabilities,
1 student with disabilities) were assigned to the experimental group where co-teaching was
implemented by special and general education teachers and the comparison group. Means and
standard deviations between pretest and posttest were compared for the students without disabilities.
Mastery levels for each lesson and the classroom participatory behaviors were examined for the
student with disabilities of the experimental group. In the results of this study, first, for the students
without disabilities, significant differences were not found between both groups in the achievement
scores of korean language, but significant differences were found in the preference for it. Second, for
the student with disabilities of the experimental group, the student achieved the mastery level for a
majority of lessons. Also, the student with disabilities of the experimental group showed increases in
numbers of verbal interaction and decreases in times of problem behaviors. Based on the result of
this study, some suggestions on limitations of the study and future study were included.