My understanding (from a close friend who is a teacher) is that these metrics are difficult to implement for the more abstract disciplines such as the arts. These, then, are being eliminated from curricula since they are difficult to measure. This may not initially appear to be an issue but the article itself illuminates a greater need for holistic perspectives on education. Putting educational disciplines in silos is damaging the experience (can't read a word problem for math) and phasing out arts may be stunting the ability to learn.
