Spain is a civilised country, not a collection of mud huts filled with simple, stupid peasants - the law on drinking in clubs is the same as any other European country, i.e. over-18's only.
If you are under 18 in Spain you are still classed as a minor. and can be sent to a minors detention centre if you commit an offence and are arrested by the police see entry on the FCO web site
They are getting stricter. You are classed as a child in Spain!
Some places are strict, some aren't.
So, basically, you are asking us for permission to break the law?
I'm 16 and my friends 18 and we want to go. how strict are they in clubs in Ibiza? when I dress up I look 18 definitely. I'd like to know from someone who's worked, had experience or been to Ibiza :) thanks!