Purpose: Jigsaw is a popular cooperative method, but its effect on students' motivation in physical education (PE) remains uncertain. The purpose of this study was to estimate this Jigsaw effect and to explore whether the type of sport taught in PE modified this effect. Method: Overall, 136 middle-school students participated in two PE sequences in Jigsaw or control conditions, one in gymnastics and one in racket sports. These two types of sports were selected because they are frequently taught in PE and for their opposing characteristics. Students' motivation was estimated during the third and sixth lessons of each sequence with a subjective measure, that is, situational interest; moderate to vigorous physical activity was added as an objective measure related to motivation. Results: Compared to control conditions, Jigsaw progressively enhanced moderate to vigorous physical activity and the novelty dimension of situational interest in gymnastics, whereas it undermined moderate to vigorous physical activity and the challenge dimension of situational interest in rackets. Discussion: We discuss the decisive role of the type of sport according to their characteristics when implementing Jigsaw.