Given that you somehow have administrative rights over the Chromebook, and the school IT department simply blocked websites at a device level, you can dig into the settings and remove any website ...

In most cases, websites are blocked using domain names through DNS ... Proxy servers are primarily used in schools and universities to block specific websites. However, using the same proxy ...

Nationally representative survey data from The Center for Democracy & Technology finds schools subjectively and broadly block students from information online.

If your school allows the use of USB drives ... Instead, you input the URL of the blocked website into the proxy website. The proxy then makes the request to the internet on your behalf.