[ZoFreX]

In the UK there is some sort of electronic cash (I forget the name) that can be bought using cash in almost every newsagents. These can in turn be exchanged for bitcoins online. Pretty simple!

That said we also have pre-paid debit cards in some stores now, so it's even easier to have one of those.

(Also it is not uncommon at all for teenagers to have a debit card)

[Jekyll]

You mean Ukash? Despite that, there is still a gap for prepaid Bitcoin gift cards which should be filled.