Teachers have the ability to link their Google Drive to their Classroom accounts which allows them to create and link Google files to assignments for students to submit via PupilPath. You can find instructions detailing how to link required submissions here How to Create Required Submissions.
Once an assignment is saved that contains a Required Submission or allows a misc. upload file, it will appear in the gradebook with a grey icon indicating that the student has not edited the assignment. When the student has edited their copy of the file the indicator will turn yellow. After the submission has been reviewed the indicator will turn green.
To view the submission click Grade>Submission or double click the cell in the Gradebook.
Once on the submission page you can cycle between students and assignments to view student work.
Note: Co-Teachers need to link a Google account to Classroom in order to see the student file.