The Delhi Directorate of Education (DoE) Wednesday directed all schools to conduct hybrid classes for students up to class 9 and that of class 11 after curbs under stage four of the Graded Response Action Plan were invoked in the city amid a sharp dip in air quality. Calm winds, low temperatures and foggy conditions allowed the accumulation of pollutants in the region, with the air quality index soaring from 275 on Tuesday to 396 at 6 pm on Wednesday. The India Meteorological Department and the Indian Institute of Tropical Meteorology predicted that AQI may breach the 400 mark soon. Accordingly, the Commission for Air Quality Management (CAQM) directed authorities in Delhi-NCR to "straightway invoke" all actions under stages 3 and 4 with immediate effect. In a circular, the DoE stated, "All heads of government, government-aided, unaided private schools under DoE, NDMC, MCD, and the Delhi Cantonment Board are directed to conduct hybrid classes for students up to Class 9 and 11, ...