This paper introduces "The Manual for Indoor Air Environment (IAE) and Ventilation in Schools", which was presented as the outcome of our working group's activity on IAE in schools organized under the auspices of the Architectural Institute of Japan (AIJ). The manual consists of five chapters. It begins by pointing out IAE issues in schools in the first chapter and presents the actual conditions of heating, ventilation and air-conditioning (HVAC) systems' installation in schools all over of Japan in the second chapter. International regulations and standards concerning IAE in schools are reviewed in the third chapter and the results of field measurements in several areas are shown in the 4th chapter. The final chapter explains the use and maintenance of HVAC equipment and the control of IAE. This manual was published in plain Japanese with many figures and it was intended for teachers and school staff, who are able to create comfortable indoor environments for children by operating and managing HVAC systems in accordance with the situation at hand.