Block websites on a limited account

I was recently promoted and will have several interns working under me but we will all be sharing a computer.

I have created two accounts on this computer. Mine (admin) and theirs (a limited account).

I am trying to block access to certain websites on the limited account but when I can't seem to block them on JUST the limited account, it always messes up my account as well.

I originally tried loggin into thier account, going to "tools", to "internet options", to "content", clicking "enable", and adding the sites I want blocked and clicking "allow never" but then it tells me I must be logged in as an administrator to make those changes. So I logged in on the admin account and tried it all over again but I do not see an option to block those sites on just the intern's account and not mine.

How can I do this?

Thank you very much for your help!

PS: we use internet explorer