What problem are you trying to solve with Submitty
An instructor makes a new forum thread and clicks the box to send that message as an announcement email & notification to all students. Students cannot unsubscribe from announcement emails & notifications so we know all students got the message as an email.

The instructor wants to make an important correction to that announcement (e.g., room or time change). Unfortunately, if they just reply to the thread, most students will not receive an email or notification. Students need to subscribe to receive 'reply to thread' emails/notifications. If the instructor wants to force students to receive a second email, they would need to make a new thread, which adds clutter to the forum.

Describe the way you'd like to solve this problem
When any member of the teaching staff makes a reply on the discussion forum to any currently pinned discussion forum post, let's offer an option to also send that reply as an announcement that all students immediately receive as email & notification. This should be a seldom used option, so make sure its easy to use, but also not confusing/accidentally overused.