Two step Process
1. Use the General Channel only for notices from you - and set permissions for this to happen
2. Create a Meetings channel where you are the moderator - and run meetings from there
Setting up your General Channel
- Change properties of the General channel (3 dots next to General)
- Set "Only owners can post messages"

This does mean if you post an ordinary message or start a meeting in the channel, students will be able to post. (Use Post an announcement instead) - Posting Announcements: (in the General Channel) When you post a message

- Click on the Format Symbol

- Change "Everyone can reply" to "You and Moderators can reply"

Create a Meetings Channel and set Permissions
- Create a new channel - 3 dots next to your Team name

- Give it a name (eg Meetings)
- Manage Channel (3 dots next to the Channel Name)
- Turn Moderation on and untick all Team Member Permissions

This will mean that students will not be able to add posts inside our outside the meeting
- If you would like to allow students to chat, "Allow members to reply to channel messages

- These permissions can be changed during the meeting and will take effect immediately