When the results are ready, you can download certificates for all your students in your teacher's account. The certificates are already filled out and show the students' names, scores and position in the ranking.
Go to "Contest" > "Results" and click on the small button in the bottom left corner that says "20 results per page". Select a higher number so all your students' results show on the same page. Now click "Export" in the upper right corner" and select "All students' certificates".
They will now be generated. This may take some time; once they are ready for download, you'll get an e-mail notification and will be able to download them in "Documents" in the left-hand menu of your teacher's account.