Cloud computing as an emerging technology becomes a solution due to its specific attribute like scalability and cost reduction for many educational organizations which are under the pressure of budget shortage. In the last few years it has a dramatic change from being a business concept to the general concept of growing IT industries and educational institution's parts. However, security as one of the most important issues decrease the development of cloud computing. From security point of view, a number of challenges and risks have been introduced from its protection mechanism. A new model desired result at improving the features of an existing model must be in contrast with the pivotal features of current model. As the purpose of this paper is twofold: first of all presenting a new model for the basic infrastructure of cloud with its unique security models and requirements that can be utilized in our educational institutions. Secondly, it is argued that it can be viable solution for many educational establishments in difficult financial time where the use of computer by students and teachers is immense. Furthermore, some especial aspect of cloud and its security is highlighted and then some light shed on the current constrains and concerns