List of Articles 21st century Open Access Article Abstract Page Full-Text 1 - A General Theory for Cities of the 21st Century (Peter Hall) and Adaptability to the Conditions of Iran Zohreh Davoudpour Daryoush Ardalan Open Access Article Abstract Page Full-Text 2 - Presenting A Model of Innovation in Secondary Education Based on Cloud Computing Technology Mohammad Mousa Shabanian esmaeil kazempour Zohre Shakibaei Open Access Article Abstract Page Full-Text 3 - Designing, a leadership pattern in the 21st century for primary school principals (Sample study elementry education of Tehran) soraya bajan abbas khorshidi Batoul Faghiharam Nader Barzegar Esfandyar Doshman Zyari