In Australia, the head teacher is sometimes in charge of one (in the case of a major subject) or multiple (often in smaller schools) specific departments, such as English, history, maths, science, writing, technology, etc., but maintains full teaching duties and status.
Rapid demographic changes in the United States have resulted in an increasingly culturally and linguistically diverse Pre K-12 student population, so classroom teachers and principals in the U.S. are not only focusing on instructional issues, but also need to increase educational leadership[whose?
While there has been considerable anecdotal discussion about the importance of school principals, there has been very little systematic research into their impact on student outcomes.
This outcome-based approach to measuring effectiveness of principals is very similar to the value-added modeling that has been applied to the evaluation of teachers.
[clarification needed] Some principals have focused their efforts on creating more inclusive schools for students with disabilities.