If you want students to create a copy of a Google Doc, Sheet, Slides, or Drawing, you can replace the /edit at the end of the link with /copy.
To make that easier, I've created a bookmarklet. To set it up for yourself, drag the following link to your bookmark bar or menu:
Then when you have a Doc, Sheet, Slides, or Drawing open (and you've set the sharing permissions) you can click the bookmarklet and it will generate a link that you can copy and send to your students. When they click the link it will prompt them to make a copy.
