What is Quality? What are the Qualities of Quality?

Harvard's Project Zero has just released The Qualities of Quality: Understanding Excellence in Arts Education. How do we create and sustain high quality arts instruction? And what is it, anyway?

Here's one small tidbit from the press release.

Quality reveals itself “in the room” through four different lenses. There are multiple dimensions of quality in arts learning experiences. Four lenses were found to be especially useful in focusing attention on different aspects of excellence in arts education settings: learning, teaching, classroom community, and environment.