The document discusses the changing role of teachers in the 21st century. It contrasts traditional teaching, which focused on memorization and was teacher-centered, with modern teaching which emphasizes student-centered learning, higher-order thinking skills, collaboration, and the use of technology. The document outlines eight key challenges modern teachers face: teaching in a multicultural society, teaching to standards, teaching for construction of meaning, teaching for active learning, teaching with varied abilities in mind, teaching with student choice, teaching with accountability, and teaching with technology.