For early childhood, the domain of geometry and spatial reasoning is an important area of mathematics learning. Unfortunately, geometry and spatial thinking are often ignored or minimized in early education. We build a case for the importance of geometry and spatial thinking, review research on professional development for these teachers, and…

Approaches to standards, curriculum development, and pedagogy are remarkably diverse; however, recent years have seen a growing movement to base each of these on learning trajectories. In this paper, I discuss and compare the various terms and conceptions of this construct, present our definition, differentiate between our conception and that of…

Investigated development of ability to recognize, anticipate, and plan the replay of recorded action sequences. Effects of an educational intervention on this ability were evaluated for two- to five-year olds. Results suggest that representational competence is a teachable concept and that a complex mediating structure allows children to…

Building Blocks is a National Science Foundation-funded project designed to enable all young children to build a solid foundation for mathematics. To ensure this, we used a design and development model that drew from theory and research in each phase. Our design process is based on the assumption that curriculum and software design can and should…