Just depends where you go, could get lucky or they could be strict. I'd wave a guess by saying if your brothers look responsible then they might let you off but they certainly won't serve you anything particularly strong. Just try and maybe you'll get served if not you'll have to buy it and take it back to your hostel
edit: listen to people who have been recently because they got stricter about a year ago and tend to get even stricter during summer as well
Its true, they are getting stricter.
When I was there last year, one of the owners told me they check majority of youngsters now because the police or their equivalent of trading standards do checks and if they are caught out they can get in serious trouble.
You don't get ID'ed in Europe 90% of the time. Also, why not be honest and say what you're really doing?
how much more honest can I be? i thought people would understand coffee shops in amsterdam means smoke up.
this is a little bit of a bummer. ill try to figure out something though because I am going as a 17 year old and who knows if I will ever be in europe again. I have to make the best of it.