The purpose of this review was to organize the results of studies conducted during the last 18 years into a body of knowledge concerning the link between physical education (PE) and academic achievement (AA). Such knowledge may help in clarifying the role of PE in the schools, whose main focus is on improving the AA of the children. The term PE is used to denote those classes taught in the framework of a school curriculum in which physical activity is at the centre. The reviewed studies were divided into three categories: the "political", in which a rationale is provided for PE in mainly achievement-oriented academic schools (n = 10); the "interventionist", in which it is shown that PE given in accordance with a defined intervention programme influences AA (n = 10); and the "integrative", in which it is determined how physical activity incorporated into the daily routine of academic studies contributes to AA (n = 5). The significance of the reviewed studies in each category is discussed, as well as the advantages and limitations of the studies. Ideas for future research on the link between PE and AA are proposed.