Global environment is getting deteriorated at an alarming rate. Eco-school could be one of the effective solutions to protect our environment and a good sample of architecture to economize in total energies, resources and greenhouse gases. In case of our country, the study of eco-school planning is not sufficient compared with other countries, so this paper would be a good study on the indoor environment of the classroom by surveying their opinions and ideas from the group of users in elementary school. The result of this study shows that the proper installation of building equipment and nature ventilation system is necessary to provide delightful environment for the students and to save the energy. To ensure that we have adequate saving and protection, it is necessary to change the existing appraisal standard.