Despite having 'green' issues thrust at them from all angles at school and at home, I have observed over and over again that the current generation of children simply don't seem to be aware of putting what they're taught into practice.
My own daughter's not too bad at turning off lights when leaving a room, turning off the TV, keeping outside doors closed, etc - but some of her friends are appalling. But some of her contemporaries get all of the above 'wrong'. On a small scale, the energy savings are trivial, of course, and I'm certainly not picking on any specific individual.
But multiply this up by 100s of millions of children across the Western world and then multiply this again by a decade or two of energy neglect and it's clear that, however bad an energy hole we're currently in, things are going to get a whole lot worse unless the current generation of children and teenagers start acting more reponsibly towards finite resources.
Of course, once the power starts getting cut off to their Playstations and TVs and once they hit adulthood and have to start actually paying their own heating bills...