Curiosity has received increasing attention in the educational literature, yet empirical investigations have been limited by inconsistent conceptualizations and the use of curiosity synonymously with other constructs, particularly interest. The purpose of this review is to critically examine the dimensionality, definitions, and measures of curiosity within educational settings, and address the boundaries between curiosity and interest. A systematic review of 39 articles from 2003 to 2013 revealed a reliance on self-report measures, a focus on curiosity as a personality trait, and definitions characterized by four themes, the most common of which were curiosity as a need for knowledge or information, and curiosity as a motivator of exploratory behavior. The overlap and relations between curiosity and interest are discussed, and it is proposed that an examination of (a) the role of knowledge, (b) goals and outcomes, and (c) stability and malleability provide a basis for differentiating curiosity and interest according to their essential characteristics.