Below are a few go-to Google Chrome extensions for school administrators.
My favorite screencasting tool because all of the recording and uploading is done within the Chrome Browser. Very helpful for creating quick tutorials for staff.
Quickly split your tabs into two windows. Super helpful for quickly organizing your screen.
Quickly send websites to your Instapaper account so you can read them later. Helpful for building a repository of resources.
Quickly send websites to your Wakelet account. With the extension you can organize your resources into collections that you can send out to staff.
Session Manager allows you to create groups of tabs that can quickly be opened by clicking on the session name. This is a great extension for leading professional development because it saves you time with opening up all of the windows you need.
Take a screen shot of an entire webpage with one click. You can also use this extension for quickly making PDF copies of a webpage.