The purpose of this study is to suggest a model plan for a mini school using the lower part of the apartment. In order to reach this model, firstly, the existing condition of over populated schools is analyzed, secondly, the Proper size and planning module for a mini school are suggested through the analysis of 7th national curriculum for the education, and thirdly, the model plan for a mini school is suggested using the apartment under construction. Mini school will be expected to solve the problems from over populated schools, and enhance the educational effect for the primary students.