Students' ability to operate with increasingly more complex units has been shown to be a key factor in their conceptual development. These abilities have been characterized as "stages of units coordination." This article focuses on the domain of composing and decomposing composite units. Using data from a teaching experiment with a…

Students' understanding of the meaning of the equal sign develops slowly over the primary grades. In addition to updating their representations of equations to recognize that the equal sign represents an equivalence relation rather than signaling an operation, students need to move beyond full computation to efficiently solve equivalence problems.…

Representation in science is anything that stands for something else--drawings, pictures, graphs, or other representational forms (Danish et al. 2020). Representations serve as public displays of phenomena that make aspects of those phenomena explicit (Gilbert 2008). They can serve to make the invisible visible, communicate ideas, display…

Educator preparation in comprehension strategy instruction (CSI) is essential to meeting the needs of English learners (ELs) in contemporary schools. This article provides teacher educators and professional developers with concrete examples of practices to prepare classroom teachers in comprehensive strategy instruction, based on an experimental…

Experts claim that individual differences in children's formal understanding of mathematical equivalence have consequences for mathematics achievement; however, evidence is lacking. A prospective, longitudinal study was conducted with a diverse sample of 112 children from a midsized city in the Midwestern United States (M[subscript age] [second…

Evolution by natural selection is key to understanding life and of considerable practical importance in public health, medicine, biotechnology, and agriculture. "The Next Generation Science Standards" (NGSS) include natural selection among several evolutionary concepts that all third-graders should know. This article explores a novel…

Recent science educational reforms in the United States have prompted increased efforts to teach engineering design as an approach to improve STEM (Science, Technology, Engineering, and Mathematics) learning in K-12 classrooms. Teaching design in early grades is a new endeavor for teachers in the United States. Much can be learned from design…

Word problems for English language learners (ELLs) at risk for math disabilities are challenging in terms of the constant need to develop precise math language and comprehension knowledge. As a result of this, ELLs may not only need math support but also reading and linguistic support. The purpose of this study was to assess the effectiveness of a…

In the earliest days of American education, leaders in educational theory and practice believed that the curriculum should revolve around the child's lived experiences. Geography, therefore, should hold a prominent place in the curriculum since it is through geographic concepts that children first experience the world around them. Reading and…

Developmental studies on heuristics and biases have reported controversial findings suggesting that children sometimes reason more logically than do adults. We addressed the controversy by testing the impact of children's knowledge of the heuristic stereotypes that are typically cued in these studies. Five-year-old preschoolers and 8-year-old…

After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed…

To date, a number of studies have demonstrated the existence of mismatches between children's "implicit" and "explicit" knowledge at certain points in development that become manifest by their gestures and gaze orientation in different problem solving contexts. Stimulated by this research, we used eye movement measurement to…

This document offers a planning tool for grades 3-7 that can be used by regional comprehensive centers, other technical assistance centers, and state departments of education to plan professional development for teachers. It is based on the "National Mathematics Advisory Panel Report" which was published in 2008. The panel synthesized its final…

This book examines learning science from multiple perspectives--especially a child's. The whimsical character of Mary Froggins guides readers through the steps of igniting students' natural sense of wonder, incorporating brain research, integrating science concepts with other subjects, and applying science to daily life. The authors demonstrate…

As environmental changes become a significant societal issue, elementary science curricula need to develop students' understanding about the key concepts of energy and climate change. For teachers, developing quality learning experiences involves establishing what their students' prior understanding about energy and climate change are. A survey…