Go to classroom.google.com.
Click the class> Classwork > the assignment.
To attach an item:
Under Your work, click Add or create > select Google Drive , Link , or File .
Select the attachment or enter the URL for a link and click Add.
Note: You can't attach a file you don't own.
To attach a new doc:
Under Your work, click Add or create > select Docs , Slides , Sheets , or Drawings .
A new file attaches to your work and opens.
Click the file and enter your information.
Note: You can attach or create more than one file.
(Optional) To remove an attachment, next to the attachment's name, click Remove .
(Optional) To add a private comment to your teacher, under Private comments, enter your comment and click Post .
Click Turn In and confirm.
The status of the assignment changes to Turned in.