What makes a highly qualified teacher?

The “highly qualified” teacher requirements defined by the No Child Left Behind Act have, like so many parts of NCLB, come under serious scrutiny. Though some people say the current requirements prevent many qualified individuals from joining or staying in the profession, others contend that they don’t do much to ensure that all students have effective teachers.

One of the current proposals for NCLB revision, the All Students Can Achieve Act of 2007, suggests teacher quality should be measured by the educator’s effect on student achievement, rather than by credentials alone. If you had to rewrite NCLB’s requirements for teacher quality, what would you include? Tell us what you think.