Some clearly think not. The first thing many grant-maintained schools do when they gain financial flexibility is increase their investment in in-service training and support. The Pounds 400 million is only half the total local authority expenditure on administering and inspecting teaching, and there is a further Pounds 100 million spent by the Office for Standards in Education.

Investment in teacher development amounts to about Pounds 53 a pupil each year, compared with Pounds 75 a pupil on books and equipment and Pounds 80 on school maintenance. Though it probably does not appear as such in school budgets, professional development is supposed to account for about Pounds 50,000 a year in a 1,000-pupil secondary or Pounds 10,000 in a 200-pupil primary.

Baker days account for about half of that. Whether it realises it or not, a 50-teacher secondary school is regularly spending the equivalent of Pounds 25,000 a year on these eponymous closure days in that most precious of currencies - teacher time. And yet according to the Teacher Training Agency, little or no effort goes into evaluating its impact in the classroom. Only one in ten schools apparently has any procedures to examine its effect in the classroom.

The agency has just completed a review of continuing professional development which revealed a widespread lack of planning, too little attention to teachers’ needs, and insufficient concern about how in-service training contributed to improving teaching and learning.

“We do not have a systematic approach to continuing professional development, ” according to Anthea Millet, the agency’s chief executive. “In far too many schools the outcomes of appraisal do not lead to action and are not being linked either to school development planning or teachers’ own professional development plans,” she concluded after a MORI polling organisation survey for the TTA found startling disparities between heads’ views of in-service development and that of their staff.

Of course, like any attempt to quantify qualities, the TTAMORI survey can be criticised. Asking a teacher what happened on a Baker day has been likened to a parent asking a child what he or she did in school today (“Nothing...”). But when two thirds of heads say all five Baker days are used for professional development but only about a third of teachers do, it raises questions about the clarity of purposes and skills of leadership of those responsible for this training. Whereas two out of three heads claimed continuing professional development was linked to teacher appraisal, only one in eight teachers thought it was.

The TTA has rightly identified, then, the need for more investment in the infrastructure of teachers’ professional development to help schools clarify objectives. It intends to establish standards for what teachers need to be able to do and know when they are newly qualified, and then later in their career to be regarded as “experts” at the levels of teacher, subject leader and whole-school manager. It is calling for more work on developing techniques for assessing teachers’ training needs and for evaluating the effectiveness of the training offered. And it has suggested that training providers should be more closely monitored.

But while the TTA has urged that school leadership and management be among the top priorities for professional development, such efforts as there are continue to focus upon new and aspiring heads. Little or no attention is given to heads already in place.

Yet, as the TTA’s survey has indicated, effective professional development of teachers rests crucially upon the credibility and effectiveness of their leadership, as well as the quality of any particular training offered. And as other research has shown, heads and senior managers, whether through selflessness or complacency, tend to consider their own professional development needs last or not at all.