I don't know what the standard practice is nowadays, whether all schools do maintain a 'gifted and talented' register or not.

I just know that a friend's teenaged son who is diagnosed with ADHD is often considered to be and treated as though he is naughty/bad instead of being considered as though he needs heaps of extra stimulation and challenges.

Mainly, though, I was going off my own experiences, which admittedly were quite some time ago.