Education and educational spaces in any eras have had a significant role in the growth and development of communities. Schools are the best-known educational spaces, which were undergone essential changes over time in various fields including architecture. Thus, it is important to evaluate these changes during different eras. The lack of spatial qualities and replacement of other segments are our schools today problem, compared traditional schools. In other words, the qualities existing in traditional schools are absent in architecture of today’s schools, and the other elements were replaced. Studies that have been conducted regarding schools to date show that less attention has been paid to architecture and content changes of schools, and their cause during different periods. Thus, it is necessary to evaluate these developments and their reasons. This paper tries to examine these developments and their causes. The aim of this study is to evaluate changes in the architecture and content of schools and the relationship between them in the traditional, transitional, and modern era in Iran, compared to each other. In this study, a comparative-analytical research methodology has been used. Library studies were used to collect data. Dodar, Chahar Bagh, and Aqabozorg schools, from traditional era, Darolfonun School from transitional era and Markar School from modern era were selected for comparative analysis purposes; then the required indexes determined for comparison and the evaluations were carried out. According to the hypothesis of this study, compared to the traditional era, architectural developments in Iranian schools during the transitional and modern eras are mostly affected by their content; nevertheless, results do not support the hypothesis and therefore, it was rejected. The results showed that the architectural changes and the pattern of Iranian schools during the transitional and modern eras compared to traditional era were associating with an abstraction-oriented imitation from the architecture of the West and the lack of traditional schools spatial qualities in the architecture of modern schools. Therefore, the same applies to the elimination of the residential section and the contents had no effect on these changes. In this way, the Iranian school has maintained the traditional pattern until mid-Qajar, but since this era onwards and with the establishment of Darolfonun and utilizing the West architecture, the architecture of schools were change. In other words, the new structures of schools during the transitional and modern eras, was a European imitation through eliminating the residential section (school-chamber) and converting to the (school-corridorclass).Thus, the spatial qualities of traditional schools were eliminated, new elements were replaced, and modern schools with new architectural were formed.