and clothing sizes

Yeah I agree, best to charge for weight rather than age per se. I mean take for example some ectomorphic little old person, and a plump endomorphic 7 or 8 year old. There's a probable chance the younger one's going to be heavier.

I think it should work like that with clothing sizes too. The independent system adopted for "children" in some countries is nonsensical. I've seen it all too often a mother going in to buy her 7 year old a pair of pants "for age 7" on the size tag, only to find out that it's far to large or small. I think clothing sizes for children should be changed over to the measurement system used for adults. There should be ONE universal clothing size system--that would make things a LOT easier for the clothing industry and consumers alike. There is no more an accurate arbitrary clothing or shoe size for a 5 year old any more than there is for a 45 year old. People of all ages and races simply come in many different shapes and sizes.