Advanced users utilize web proxies or Remote Instruction Network Services (RINS), which act as intermediaries. The student connects to the proxy (which may be unblocked), and the proxy fetches the content of the game. This masks the destination of the traffic from the firewall.
When the official domain is restricted, several alternative platforms host the game. These sites often use mirror links or different domains that might not be flagged by standard filters yet. Cookie Clicker cookie clicker unblocked site