The ability or inclination to think about thinking is not necessarily innate. It needs to be nurtured. It is not age but experience that enables learners to use appropriate learning manoeuvres successfully.
It is not just a matter of teaching skills or strategies, important as this is. It is about creating powerful learning environments for thinking: from ways of knowing to ways of being.
In every subject area we can apply such strategies as asking open questions, encouraging students to plan ahead and monitor their own performance, and to identify sources of difficulty, and to check, revise and self-test. Skills are specific to a particular subject area and essential to learn; but these strategies are super-ordinate skills, generalised procedures not confined to particular curricular areas. They need to be made explicit. When children are expected to reflect on their own thinking they begin to know what to do when they don’t know what to do. They are in process of becoming autonomous independent thinkers.
Even more importantly, teachers need to inspire students with enthusiasm for the subject, so that they desire to continue learning. And that takes me back to the first question about empowerment.