This is an excellent post from the "Moving at the Speed of Creativity" blog, though I warn you that it's a bit long. In it, Wesley Fryer writes about the positives (and negatives) of teaching after the high stakes testing periods have been completed (this period of "relief" occurs only in May).
I remember when I was in high school at Galloway that the fun really began once the AP exams had come and gone. I probably learned less about my subjects in the few weeks after the AP exams (and before the wonderful summer holiday) but that was more than made up for with extensive learning about fun, more abstract topics. Galloway is good at generally avoiding "teaching to the test", which helps because student's learn for learning's sake. This May period after AP exams that Fryer blogs about were particularly wonderful.
It'd be great if more schools placed less emphasis on testing and grades and more emphasis on learning. Of course, parents, colleges, and employers generally want accountability, so this is probably going to continue being an interesting conundrum.