If you get a chance, you should take a look at this piece on Howard Garder from Edutopia.
Here's the video and an excerpt from Gardner:
On the need for a new approach to assessment in schools.
Let's get real. Let's look at the kinds of things that we really value in the world. Let's be as explicit as we can. Let's provide feedback to kids from as early as possible and then let them internalize the feedback so they themselves can say what's going well, what's not going so well.
I'm a writer and initially I had to have a lot of feedback from editors, including a lot of rejections, but over time I learned what was important. I learned to edit myself and now the feedback from editors is much less necessary. And I think anybody as an adult knows that as you get to be more expert in things you don't have to do so much external critiquing, you can do what we call self-assessment. And in school, assessment shouldn't be something that's done to you, it should be something where you are the most active agent.