Due to new classes, I've regrouped my classrooms. how do I download new class list login info pls?
You can't re-download passwords; they're only available when accounts are newly created. After that point, a password is owned by the user, and should only ever be known by them.
You can see the list of students and their usernames by clicking on your classroom. With any luck your students will remember their passwords, but if not, you can reset them through the Duolingo for Schools interface.
I generated a new list of students for a classroom, but the list of logins and passwords did not appear. Now what do I do?
Do you mean you created accounts for your students? As well as giving you the PDF to download, the system emails that list to you. All you need to do is check your email.