I have user based access control on my 2830n. If I give my son 2 hours, once he logs in, how can he log out?

(I have the auto-timeout set to 0/unlimited because when it was set to 10 mins, it was disconnecting his online gaming after 10 mins. I am correct in thinking the router only makes the decision as to whether the PC is in use based on browser activity?)

It seems like I need to give my son an URL he can lock on to log out if he finishes his session whilst he still has time left.

Thanks,
Seabro