Do I make him pay it with his own money to make a point?
He's been phoning his school friend and then leaving it on speaker phone whilst they just play computer/DS Lite games and pretend that they are sitting in the same room So, no active chatting IYSWIM. I suspect his friend's phone bill is equally high, if not higher.
I have banned him from phoning the friend during the week given that they've just spent X hours at school together!)
I thought this wasn't meant to start til they're teens!
I don't think I am going to make him pay BTW because the money isn't really an issue. It would be nice to just make him think about what things cost though.