Harold,
This made me think about measuring students satisfaction with their schooling, whether they feel the student culture is supportive of academic achievement or an obstacle to it, whether they feel safe or bullied, do they feel like they are viewed as individuals by teachers or as one of a hundred students tramping in to a class, do they feel valued and empowered or not...

Developing a healthy student culture may be a key to transforming our schools. It may be more important than any curriculum or pedagogy changes we can make.

It would be best to combine all three.

pete