Many schools - indeed, many institutions with any online presence - are required to have a statement on their site that describes how cookies are used and stored. A "cookie" for this purpose is not a delicious baked treat, but rather a small text file that contains information about how a user interacts with a website. Each website a person visits can create its own cookies, which are stored on the user's computer/device. Cookies can store all sorts of information about what a user clicks on a website and when, as well as unique identifying characteristics that associate a specific browser with a user account - this is how a website knows that you have "logged in" and can access restricted information.
Cookie policies typically cover generic categories of cookies rather than specifically noting every location they're implemented or what they're each used for. Here is some verbiage we composed for the finalsite.com site that could be adapted to your site as well (the below would be true for any of our sites):
Our platform uses several different categories of cookies:
Necessary for the operation of the site
Certain cookies are necessary for the operation of the site. For example, certain cookies are used to help keep track of your session status. This makes it possible for you to stay logged into the site as you move from page to page.