Start a video meeting by clicking meet. You can chose 'Meet Now' to start a meeting immediately or 'Schedule a Meeting' to schedule a meeting for the future.
Note that scheduling a meeting this way does add it to the Outlook calendar for all members of the channel, but it does not send them an email message. Instead, it sends a message to the Teams channel.
Once in the meeting, choose the 'share screen' icon.
Choose which window or application you want to share with the video meeting.
Choosing 'Desktop' will share whatever is active on your screen, while choosing a specific application will only show that window, no matter what you do in other windows on your computer. It's usually safest to limit what you share to avoid email notifications or other distractions from showing in the meeting.
You can share Powerpoint files without having them open, but all other files and windows must be open and active on your computer in order for you to share them.
On the WebApp:
Click on 'Screenshare Desktop/Window' to prompt a pop-up that will let you choose a specific application.
Sharing Your Screen on a Mac
Mac users may need to go through some extra steps to share their screens, outlined here.
If you're using the desktop app (not the webapp), you can also take (or give) control of a screen when screen sharing. This can be helpful when you're trying to walk a student through a task.
While sharing your screen or viewing a shared screen, hover near the top to activate the top toolbar. Here you can choose to give control or request control of the screen.
You will be able to interact with the other user's screen using both your mouse and your keyboard.
If you want the others in your meeting to hear sounds from your computer, such as when showing a video or listening to music, you'll need to check the 'Include System Audio' box when setting up your screen sharing.
This option is not available via the webapp; you can only access it from the desktop version.