A comparison and contrast is made between different notions and occurrences of play in daily life to highlight the sense of the importance of play in a physical education lesson. The meaning and definition of play are detailed, and its impact in and as part of actual learning is discussed. Two stories of real-life situations are described in which children are "coaxed" into play as a cover for a physical education exercise. These two examples suggest that the actions of the teachers, as privileged spectators and conductors of play, have enabled every child to realize (in a physically dominated way) the social reliance, to and fro relationship, serious focus, and double meaning of play in a physical education lesson. It is hoped that the report will help teachers to reinterpret what play means and to re-value the role of play in physical education. Serious play can create situations of physical, cognitive, emotional, and social danger; it is up to the teacher's reflexive attention to the lesson to skillfully channel this danger into opportunity. (Contains 14 references.) (NAV)