The head of the Secondary Principals' Association says children are being over-diagnosed with learning difficulties and those who are not could be the ones who suffer.
Tom Parsons said children may have learning difficulties or be classed as gifted-and-talented, but the children in between needed just as much resourcing.
He said he could not comment on reported figures showing cases of attention deficit disorders had risen from 5000 to more than 120,000 in 11 years.
But, Mr Parsons said children were being stigmatised away from normal, which was not helpful for them when they left school and enter the workforce.
He said the problem was big lobby groups pushing for more help for those on the bottom end of the scale as-well-as for gifted students.
It was a competition for scarce resources, and it was important not to forget the students he called normal, he said.
"I would argue that the pendulum has swung a little too far on kids that are being stigmatised away from normal.
"And it's important for us not to lose sight of the huge number students that are actually normal."
