how do i send an email to
a. one student
b. all students in a class
The short answear is "NO". You can't send email from Canvas.
The way it works in Canvas is that you send a message trough the Inbox (How do I send a message to a user in a course in the Inbox as an instructor? )
The user decides whether they get notified about the message in the browser, in the app, by SMS and/or by email. (How do I set my Canvas notification preferences as a student? )
By default they will get an email saying that they have gotten a message.
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