RIght now, users have to be added individually. Support for Distribution groups should be added shortly.
However there are multiple workarounds:
1) Do not invite any users, and instead place the meeting in a specific Teams channel. The students will see a link they can click on to join the meeting.
2) Create a meeting from your Outlook Calendar and set it as a teams meeting type. Then select students from there - distribution groups work from Outlook.
3) Schedule a meeting in Teams on the Calendar and make sure you select a Teams Channel as part of the meeting setup. . Then go back to the Meeting , and copy the 'Join Microsoft Teams Meeting' text from the bottom of the meeting window, and email this link to students using email, or past it into chat.
