As much as I complained about them at the time, the education classes I had to take to get certified did have some highly useful concepts. One of those was the distinction between convergent learning (where you want all students to reach the same final answer) and divergent learning (where you want each student to come up with a unique answer). Before you made a lesson plan or write a test, you were supposed to ask yourself where you want to see convergence and where you want to see divergence.
[There is an obvious connection between this divergent learning and the creativity discussion here, here, here and here]
There is an common but fatally naive misconception that convergent learning goes with math and science while divergent learning goes with arts and humanities. Almost all subjects start with a large convergent learning component including the arts (try picking up an instrument and see how much divergence your teacher tolerates in the first few lessons). More importantly, ALL subjects are fundamentally divergent at a high enough level. Writing a novel, composing a symphony, proving a conjecture or designing an aircraft are all creative exercises in constrained problem solving. We demand that certain conditions be met but we expect that each solution (or at least the method behind it) will be unique.
Which begs the disturbing question: will the proposed educational reforms produce more or fewer of the divergent thinkers we actually need?
p.s. Liam Hudson came up with a uses of objects test to measure divergent thinking. It ignores the complex interaction between possibility and constraint and is therefore, in my ever-humble opinion, complete crap, but take a look anyway.