ID card for 15yr old

[sorrento24]

My 15 DS is 6ft plus and looks older than he is. Does anyone have any experience of ID cards for that age group? A quick look online shows the Citizencard which says it's police and Hone Office approved but I'd be interested to hear if anyone's kids have one and how it is received when shown as proof of age?

Free railcard id from train stations, DS has one for his 'child' tickets. Works on the train, we haven't tried it elsewhere.

He'll be 16 soon & we have to pay full whack , but at least he could prove he was under 16 until then.