For questions specifically about working with the Google Classroom app.
Classroom is available to anyone with Google Apps for Education, a free suite of productivity tools including Gmail, Docs, and Drive.
Classroom is designed to help teachers create and collect assignments paperlessly, including time-saving features like the ability to automatically make a copy of a Google document for each student. It also creates Drive folders for each assignment and for each student to help keep everyone organized.
Students can keep track of what’s due on the Assignments page and begin working with just a click. Teachers can quickly see who has or hasn't completed the work, and provide direct, real-time feedback and grades right in Classroom.