Curriculum narrowing leads to more time spent on tested areas, like mathematics and reading, and less time on nontested content, such as history. As a consequence of accountability systems, teachers may overemphasise certain subjects that will be tested, even if they make up only a small part of the entire curriculum (Eurydice, 2009). In addition, specific subjects can be omitted from the lesson plans as tested areas are given increasing priority (King and Zucker, 2005).