Google Classroom

Google Classroom is a free web service developed by Google for schools that aim to simplify creating, distributing and grading assignments in a paperless way. The primary purpose of Google Classroom is to streamline the process of sharing files between teachers and students.

Google Classroom combines Google Drive for assignment creation and distribution, Google Docs, Sheets and Slides for writing, Gmail for communication, and Google Calendar for scheduling. Students can be invited to join a class through a private code, or automatically imported from a school domain. 

Each class creates a separate folder in the respective user's Drive, where the student can submit work to be a graded by a teacher. 

Teachers can monitor the progress for each student, and after being graded, teachers can return work along with comments. 

(source: http://bit.ly/2I9jmkT)