I think it is important for all children to have good, realistic careers advice, which allows them to get an insight into the realities of various careers - i.e. Some careers will require very long hours/anti-social hours/only be possible to work in central London/large cities/involve lots of overseas travel, and others will be more flexible.
I had a friend who chose to become a dentist, right from school age as she knew it would be possible to have a good lucrative career on part-time hours, she could do it in any part of the country, and she knew she wanted a job that would fit in around having a family eventually. And guess what? She was right! She pretty much 'has it all' in my opinion.
Far better in my opinion to think and plan ahead, than sleep walk into a situation where you are in a career which is not really compatible with family life (and your partner is the same), and you are stuck having to make the choice between pursuing decent career (not necessarily super high flying - just decent) and being able to take the time to be available for your kids and doing some crappy, low paid, 'mum job' despite being highly educated. And to be fair, why should any man be in that position either?
It was never even a consideration when I was at school how my career choice would be affected by having a family - I wish it had been. It's all very well saying it shouldn't be, but for many many people, the reality is that their careers have dive bombed because whatever they chose to pursue was just not compatible with having a family when the other parent was working in an equally inflexible career.