I have just been reading this pdf file from Elena Silva which is very interesting and has implications for all educators.
"Skills that really matter for the 21st century—the ability to think creatively and to evaluate and analyze information—can be measured accurately and in a common and comparable way. These emergent models also demonstrate the potential to measure these complex thinking skills at the same time that we measure a student's mastery of core content or basic skills and knowledge. There is, then, no need for more tests to measure advanced skills. Rather, there is a need for better tests that measure more of the skills students' need to succeed today. … "
It is interesting to note New Zealand's standing in this table.