Knowledge storage system for school ERP

Please understand the requirement before bidding. We have school ERP(built on codeigniter framework) and we require a content storage and display system. This content will include stuff related to educational institutions like PDFs, Documents, Flash movies, Educational videos, PPTs, images etc. We have thought of storing this (potentially huge) data on cloud based storage (Google drive, Dropbox, etc). After this content is stored by admin/teacher on cloud storage, permissions will be assigned to them. For example contents in Folder ABC can be accessed by student of class 4 and 5 only. After assignment of permissions by admin/teacher, students will be able to view content through their portal. Lastly students can also upload any content. Admin will have right to approve or reject the content before it gets uploaded. We'll share the details of Student, Parent and Teacher table(table fields) once project is awarded. Many Thanks! Virendra