Swing
Montessori describes a swing with a push-off board (page 59, "The Montessori Method").
Seguin describes a swing with a spring-board and a pulley. (page 84)
Montessori describes a swing with a push-off board (page 59, "The Montessori Method").
Seguin describes a swing with a spring-board and a pulley. (page 84)