Learning progressions (LPs) are cognitive models that describe the development of scientific knowledge and practices in students. They are constructed based on learning theories and student data. Scholars have advocated for using LPs to align curriculum, instruction, and assessment into a coherent system, and by doing so, promote productive…

This study aims to explore how a research-informed product, a hypothetical learning trajectory (HLT), was implemented by a group of Shanghai teachers in mathematics classrooms and promoted by a researcher through a Chinese lesson study. The instruction informed by the HLT served as a boundary object to promote conversations between the researcher…

This paper comprises the results of a design study that aims at developing a theoretically and empirically based learning trajectory on statistical inference for 9th-grade students. Based on theories of informal statistical inference, an 8-step learning trajectory was designed. The trajectory consisted of two similar four step sequences: (1)…