If a participant is no longer in your class and you want to remove them so they no longer receive announcements sent to that class, you can easily do that within your account. Only class owners can remove participants from a class. When a participant is removed, they will be notified they have been removed.
On the App
To remove one participant, tap the class you need to remove them from then tap the "People" tab. Find their name in the list then hit the 3 vertical dots next to their name and choose "Remove from class."
If you need to remove all participants in a class, you should archive the class. Just select the class from the menu and tap the name again at the top of the screen. On the class info page tap "Remove from class list" and confirm the change.
Click the People tab on the class and find the participant(s) you wish to delete.
To remove one participant, click their name, click on the three dots button on the right side panel, and then "Remove from class."
To bulk remove participants, click on the circle left of the participant names for each participant you would like to remove. This should select each participant like below. Then click "Remove" in the right panel to bulk remove the participants from the class.
If you need to remove all participants in a class, you reuse the class code. Click the gear in the upper right for the class you wish to delete. Click Reuse class code which will remove all participants, archive that class, and create a new class with the same code, name, and icon. Confirm and you're done!