A fair and equitable distribution of educational opportunity could be classified under the term sustainable development. Each student from any social and/or economical class should be able to have a fair chance to access to suitable educational opportunity. In this paper, a mathematical optimization model is proposed to determine the share of each social class in each state-owned school. The share is based on the student population in each class. The model also minimizes the total transportation distance in order to decrease the environmental impact of the solution. The proposed model is used in
a real case study in the city of Bushehr in Iran.