Clicking on the Paper Clip icon for attaching items does nothing.
As of April 2015, Chrome no longer supports the NPAPI plugin, which is what powers certain features in Exchange 2010's Outlook Web App. This affects the following when creating a New email: Attaching items, Saving as Draft, Inserting Image, and Open Address Book.
Open Internet Explorer:
Navigate to either:
Log in with your credentials, and you should now be able to attach items in webmail.
The Outlook Program on your computer should natively be able to attach items to emails without issue.
You can find this program by hitting the Windows (Start) Key:
Typing "Outlook" into the search bar:
You should see the icon pop up in the search results as either "Outlook 2007" "Outlook 2010", "Outlook 2013", or "Outlook 2016".
This program is pre-installed on all deployed staff and teacher computers, but not on student computers.