Ubuntu Firewall

I am using ubuntu server as firewall with 3 interfaces (interface for students and another for teachers and DMZ) in VMware, I want to block Facebook website for customers of eth1 then I used this rule:

iptables -A INPUT -j DROP -p tcp --destination - port 443 -i eth1

But it did not work and the customers of interface eth1 alwaysaccess the site, how block sites for clients of eth1 using rules IPtables ?