YouTube in Education
Customize Your Channel
Click the blue Add Channel Art and use the gallery to choose your design for the optimized picture.
In your videos, an unlocked button on videos means it's unlisted which means you need a link to see the video, the locked button means the video is private, and a video without a lock or a globe means it's public.
In your playlists, you can add videos and collect them into a playlist like an album based on a subject. Your saved videos or playlists can be unlisted, private, and public. YouTube says that you can share private videos with up to 25 people, but so far, I haven't been able to share private videos or playlists. In order to share, you need to save it as unlisted.
You can only change what you upload on your channel. What you change will not affect other channels.