Educators have long been aware of the importance of critical thinking skills as an
outcome of student learning. More recently, the Partnership for 21st Century Skills has identified
critical thinking as one of several learning and innovation skills necessary to prepare students for
post-secondary education and the workforce. In addition, the newly created Common Core State
Standards reflect critical thinking as a cross-disciplinary skill vital for college and employment.
Despite widespread recognition of its importance, there is a notable lack of consensus regarding
the definition of critical thinking. The purposes of this literature review are to (a) explore the
ways in which critical thinking has been defined by researchers, (b) investigate how critical
thinking develops (c) learn how teachers can encourage the development of critical thinking
skills in their students, and (d) review best practices in assessing critical thinking skills.