Curse you debit mastercard

Have you seen the ad? It says something along the lines of how can your debit mastercard help you live the life of a rockstar? So you go out buy a drumkit with your DMC, practice, practice, practice, get your first gig, tour over seas, trash motel room and pay for it with the debit MC...

It of course, made F's little ears prick up. He says to me the other day:
"Mum, what is a debit mastercard and how do I get one?" I asked why, and he said he wanted to do a 'gick'.
"Whats a gick F?"
"You know, a gick with my drums? What is a gick, Mum?"
I thought about it for a second, then recalled the ad and explained that first gigs were often done at pubs or on the street, sometimes to only a couple of people... And that the DMC card uses his own money.
"So.. my money box has to be full then? Oh good, because it has SOME money in it already!" "Yes... and you have drums now already."
"Oh cool!! Then I can do my first gick?"
"Gig, babe, umm.. yeah but remember the ad says practice, practice practice first?"
"ohhh yeahhhh, okay Mum listen to this!"
Cue drums being bashed for oh, say ten seconds or so. That's his practice. But he does it daily at least.

I am actually wondering at what age he can get formal drum lessons? He has a guitar and keyboard as well, but it is the drums he is most keen on, and shows most aptitude for. Does anyone know or have any helpful advice? I don't want to push him at all, or zap the fun, but at what age do I take him seriously?! I want to encourage him and his dreams!