You can create folders to organize your collection of images.

While logged in as a teacher, go to your Studio tab, and then scroll down and click Images.

In the menu, you will see a blue button that says "New Folder" with a Plus symbol next to it; click this to create a new folder.

You can name the folder, and then it will appear in your folders list which you can access.

The red "Lock" Icon indicates an item is being used as a cover photo or profile picture. 

To add an image to a folder, click and drag the image to the folder you want the image to be in.

To remove an image from a folder, click on the Blue Minus Icon in the upper right corner of the image thumbnail.

You can Delete the Folder, Rename the Folder, or Add a New Subfolder as well while viewing it.

When viewing the contents of a folder, and you want to go back to the higher level folder, or home, click on the blue "↑Up" button, or the small "Home" icon.