I need Advice/Help from Networking Issue

i got small problem in training center
because some student is using the internet even if i teach yahoo
is there a program or in router config to block the internet “especially facebook”
example if the time 9-11am is only yahoo messenger lesson they cant access the explorer or firefox???
did you get my point?
should it be done computer by computer or just the router…
when i teach the hardware i just turn off the router but if i teach the yahoo,skype,live… i want to disable the firefox and explorer
this one work in per computer but its time consuming for 30 computer each
Open Windows Firewall with Advanced Security
Click Outbound Rules (on the left side)
Click Make New Rule (on the right side)
Make sure "Program" is selected and click Next
In "This Program Path" go to your Firefox Folder and click Firefox.exe
Block the Connection, then you'll have 3 choices I usually leave them all selected.
Name it.
Answer #1
Having trouble understanding your post.
Do you not have a network administrator? Are you the network admin?
Normally you will have the network administrator restrict access via group policy,
and block access to websites via the router/firewall for the network.
Will need details about your network in order to give you any help, otherwise any suggestions I give you will be a per-computer basis.
Answer #2
this one mate
http://r3dux.org/2009/12/how-to-block-access-to-specific-websites-from-your-router-using-tomato-firmware/
havent test it yet…
what do you think?