This chapter is devoted to creating a cloth and paper model of the river valley that provides a hands-on approach to understanding river and floodplain ecology in the Southwest. The basic activity, "Changing River," provides a setting for the subsequent activities that explore the roles of animals, plants, cottonwood trees, agriculture, and change in the river of the past (Rio Bravo), the present (Rio Manso), and the future (Rio Nuevo). By creating models of these three stages of the Rio Grande, the powerful teaching technique of contrast is used to clarify the role humans have played and can play in this river ecosystem.