The Spiral Curriculum is predicated on cognitive theory advanced by Jerome Bruner (1960), who wrote, "We begin with the hypothesis that any subject can be taught in some intellectually honest form to any child at any stage of development." In other words, even the most complex material, if properly structured and presented, can be understood by very young children. Key features of the spiral curriculum based on Bruner's work are: (1) The student revisits a topic, theme or subject several times throughout their school career; (2) The complexity of the topic or theme increases with each revisit; and (3) New learning has a relationship with old learning and is put in context with the old information. The benefits ascribed to the spiral curriculum by its advocates are: (1) The information is reinforced and solidified each time the student revisits the subject matter; (2) The spiral curriculum also allows a logical progression from simplistic ideas to complicated ideas; and (3) Students are encouraged to apply the early knowledge to later course objectives. Although there is no clear empirical evidence of the overall effects of the spiral curriculum on student learning, "features" of that curriculum have been linked to improved learning outcomes. In addition, the spiral curriculum incorporates many research-based approaches from cognitive science that have been linked, individually, to improved student performance as well.