In primary school, boys tend to only get their left ear pierced because there is still the whole, stupid "gay ear" thing - even though all my gay friends who have their ear pierced have theirs on their left side too! lol

But, once in high school boys seem to get both sides done - especially if they have those flesh tunnels/spacer things.

I personally don't like ear piercings on boys but if my daughters are allowed it and my son wants it, I would try to talk him out of it but would let him if he insisted.