I have just come across a blog 'Living in Dialogue' in which a Californian teacher - Anthony Cody discusses a recent British study  that suggests "pupils show greater motivation, are better behaved, and are more likely to be independent and strategic thinkers when teachers are not obsessed by grades."    http://blogs.edweek.org/teachers/living-in-dialogue/2010/08/children_perform_best_when_tea.html?r=100915379

"The researchers cited several fascinating experiments that shed light on what is occurring.
In one study, some teachers were told to help pupils learn while others were told to concentrate on ensuring that their pupils performed well. The students under pressure to perform well obtained lower grades than those who were encouraged to learn."

"Another study showed that when teachers focused on their students' learning, the students became more analytical than when the teachers concentrated on their pupils' exam results. A further study, of 4,203 students, showed classroom behaviour improved when teachers focused on learning rather than grades."

"Curiosity is an innate feature of our brain. But like anything, it will grow when it is exercised, and whither when it is neglected. Our obsession with test scores is killing curiosity."