Usually you can bypass filters especially in schools or restricted offices by using proxies. Proxies helps you connect to the outside world/internet even if there are filters set in place at your school. 

I usually go to proxyinter.net for their latest up to date proxy list of anonymous proxy servers on the internet. The proxies on their list is guaranteed to be alive and still working because they check and update it regularly, so you are assured you have a working proxy list at your disposal and use it whenever you want.