Inclusion Criteria:  Age of between 8 and 12 years old Males and female of ethnic Han Subjects who have no plans to change classroom during the intervention period Subjects who staying in Jiaozuo city during the intervention period  Exclusion Criteria:  Subjects with asthma, childhood diabetes, childhood hypertension, and behavioral disorders Subjects who plan to transfer or move offsite within six months Subjects who decorated or plan to decorate home within six months Subjects with smokers in the household