Teaching is one of the noble professions because the nurturing
and development of a child's potential is in their hands. A
principal sets the targets, strategies, and overall direction for
the school, and the teachers in that school has to then conform to
his/her goals. Thus a principal's actions can have far-reaching
consequences.
I shudder to think of the damage this principal has done.
lotus999's comment about this principal being more suited to a QC
job in a factory has me laughing because that is certainly a good
suggestion! 
The principal has to remember that she's dealing with influential
young people. Whilst it's true that not everyone has got what it
takes to succeed in a certain area, it doesn't mean that they won't
be absolute star performers in other areas! It's the teaching
profession's onus to help draw out the best in the students under
their care, to encourage, to motivate, and to point them in the
correct direction, and even to provide career guidance. The whole
point of the teaching profession is to nurture and educate, not to
segregate and condemn!!
To step into a classroom and basically condemn the entire class is
wrong. It sounds like a bourgeoisie telling the pleibians to not
even bother trying cause they will forever be cast in the role of
pleibians! 
I detest how this principal seems to degrade the value ITE's
contribute to society and the economy. Basically, no matter which
field you are in, you can be outstanding and you can make a really
useful contribution. In my younger years, I was a tad snobbish, but
now, I find myself realising that some of the best and most
exemplary people I've known, are the blue collar workers like our
taxi drivers, the mechanics, the technicians, and the humble and
diligent people who do maintenance and cleaning chores, the
shopkeepers, etc. I find it an absolute delight to be in their
company because they are humble, frank, and they make a decent
living through sheer diligence.
Whoever dares to snub graduates of Singapore's ITE ought to
re-evaluate their own mercenary, utilitarian, and didactic views
towards life! The Singapore govt has invested money into making our
ITE's world-class and if someone as high-ranking as a Principal has
the sheer audacity to imply that ITE's are "dumping grounds" for
students who cannot do well academically, the MOE should really
call that Principal in for a good, long talk on what a career in
teaching is all about!
It is alright to provide career counselling to a student who's
obviously struggling academically, and evaluate where her strengths
and aptitude lie, and then help her get into the ITE. We should
always help find the job that's the best fit for a person, no
matter what job it is. However, what we should never do, is to
storm into a classroom, apply Board Room tactics to scare the
bejesus out of the students, completely shatter their self-esteem,
and then leave them with the thought that they are not good enough
for anywhere else but the ITE because the ITE is the only place
that will accept people like them! Please... we're dealing with
people, with youths, and the impact on those poor students' future
and perhaps even, their lives, will be great!
The MOE should show that it doesn't tolerate such treatment of our
Singapore youths. A country cannot survive on white collar workers
alone. It's time to give due recognition to our hardworking
blue-collar workers as well.