ABSTRACT
88Learning progressions synthesize a sequence89 of increasingly complex thoughts about content over a period of time (Duschl, Schweingruber, & Shouse, 2006). Duschl et al. explain: “Learning progressions are descriptions of the successively more sophisticated ways of thinking about a topic that can follow one another as children learn about and investigate a topic over a broad span of time” (p. 218). The construction of learning progressions enables teachers and school leaders to consider how discrete student expectations as represented in standards documents are connected within and across grade levels. Learning progressions are (1) centered on big ideas in a subject area, (2) grounded in research about development of students’ conceptual understanding of these big ideas, and (3) connected to processes through which students engage with content (Duschl et al., 2006). Further, learning progressions guide the creation of aligned formative assessment measures (Heritage, 2008). In the present case, a team of middle school teachers build a learning progression and associated formative assessment activities related to ratio and proportion, a big idea in middle grades mathematics (Lobato & Ellis, 2010; NCTM, 2006).
