This study is to find out the effects difference between the cases when a teacher directly intervenes and when the Vygotsky's scaffolding program is applied to solve the students' conflicts in the class. For this purpose 292 students(154 boys, 138 girls.) of eight classes located in seven middle schools in Seoul, Gangseo - gu and Gwang-myong City were studied for 8 weeks. The results were as follows: First, in the class atmosphere, accomplishment atmosphere (p<.01 under) and overcoming atmosphere(p<.05 under) factors were higher ‘teacher scaffolding’ program that the teacher directly intervened. On the contrary, autonomy atmosphere(p<.01 under) was higher when 'classmate scaffolding' program was applied. Second, self-esteem was higher in the social ego(p<.01) and school ego(p<.05) when classmate scaffolding program was applied. Third, in the academical self-concept, the sense of competence was higher when 'classmate scaffolding' program was applied and the sense of incompetence showed no meaningful gap. This study showed that the teacher's direct intervention was somewhat effective in settling the class conflicts but the scaffolding program in which students themselves solved the problems as mediators was more effective in elevating the autonomy atmosphere and school ego or social ego as the sense of self-esteem, and futhermore, sense of competence as the learner's academical ego. In conclusion the introduction of 'classmate scaffolding' program is needed in solving the students' conflicts along with the teacher's intervention.