In the current cloud era, new cloud skills are required for IT specialists. Educational organizations such as universities need to provide an educational cloud for their students. We have constructed a private educational cloud based on the Ubuntu Enterprise Cloud. The most important feature of our cloud is super saturation, which is defined as allocating more logical resources than actual physical resources. A supersaturated cloud is able to run more than 10times the number of instances than a conventional cloud. Although there is a slight drop in performance, the cost decreases drastically. We propose a Platform as a Service(PaaS) on an Infrastructure as a Service (IaaS) (PoI) method to further improve the utilization of the educational cloud based on super saturation. In this paper, we compare two methods for creating PoI applications, Single Tenant PaaS and MultiTenant PaaS, where the former allows applications to be installed easily, whereas the latter achieves high convergence.