Such a simple statement to make but what lies behind it are the systems and structures needs to allow teachers to do just that, teach.  For students, the curriculum is their everyday lived experienced and it is teachers who create that curriculum.  Their role is integral, the impact they have cannot be underestimated, and they are at their most effective when they know what needs to be taught when and why.  In knowing this, teachers can focus on how to teach what needs to be taught.  The pedagogical choices a teacher makes not only promotes the situational interest needed to engage leaners of all abilities but are also essential in affecting the development of techniques and skills for thinking; challenging attitudes and feelings, producing academic and social skills.  Teachers create and develop the curriculum every day.  Development of the curriculum therefore rests on teacher development.  And for teachers this development is two-fold: their initial development depends on the what, where and why of the curriculum to be taught already being in place so that they can focus on developing their skills in how to teach.  This is followed by developing teachers’ curriculum expertise in what to teach where, and an understanding of why this is fundamental.