Hahah.. The first time my mum had a mobile,she phoned me to ask how to do a space when sending a text.. I told her I wasn't sure but my phone was the 0 button. Next thing I knew I got a text message like this; hello0lee0this0is0my0new0number0lots0of0love0mum.
On topic though, I think secondary school is an acceptable age for a mobile. Any younger is just silly.