im a fully qualified and experienced teacher currently working private sector education so am qualified to reply to this topic.

the two teachers who cannot hack it should be fired. there are planty of capable and qualified individuals who could do their jobs if given the chance but because of such wasters are forced to work elsewhere or take crappy part-time posts with no security or guarantee for the future.
perhaps the teachers job nowadays is harder than before but that is not saying much. 22 hrs a week of hard work for 8 months a year. poor you.
try going out into the real world and "earning" 35-60k . even without taking 4 months holidays, its not that easy.
in every staffroom ive ever been in, ive heard pretty much the same conversation.
- i bumped into so and so from colloge at the weekend. big merc,house,loads of money etc. stupid me, doing this crappy job for crappy money. i shoulda/coulda done something else and been rich like him.
reality check -
in the real world a ba/bsc plus €2.5 = a cappuccino
i know / have met quite a few very wealthy -successful people in the private sector who have all the trappings of success, cars, houses etc. i am, however still waiting to meet one that i would be envious of. without exception, they usually work every hour there is, have no lives to speak of and will probably be dead from real stress before they get to see their pension.

the only negative aspect to teaching is the difficulty in getting a proper job with security but once you are in, it is easiest job going and for what you actually do, very well paid.