The project „climate-regulated classroom“ is about regulating a normal classroom. With help of an Arduino we want to control the temperature and the concentration of CO2 in the air. If the concentration of CO2 is to high a red lamp will switch on and if the temperature will be to high a yellow lamp will switch on. The lamps are signals for the students or the teacher to ventilate. This allows the pupils to learn in a classroom with fresh air and a comfortable temperature. The Arduino get placed on top of cubicle to eliminate interfering sources like a whisper of a student.