If you created your students' accounts, then yes. When you created your students' accounts, the site offered you a PDF of that information. If you missed it at the time, that isn't a problem; the site emailed you that list - just look back in your email.
Then the only information available to you is through the Duolingo for Schools page. If you click onto More details, then Activity details, you can download a spreadsheet with names and email addresses.
I don't have the email and I I do not have the printed PDF roster (left it at school). I'm trying to get a copy of BOTH the usernames and passwords so that students can have access. Is there a way to do so?