The Tehran Province’s Governorate announced the decision after an emergency meeting to protect citizens from the thick smog in the air.
Abed Maleki, a senior member of the governorate, said the decision applies to all levels of education, from kindergartens to universities.
Many provinces in Iran have been continuously hit by sandstorms since the start of the new Iranian Year on March 21.
Authorities blame the devastating dust storms emanating from neighboring Iraq Saudi Arabia and Syria as well as dam construction activities in Turkey for the pollution that has reached hazardous levels.