This article reports on students' problem-solving approaches across three representations--number lines, coordinate planes, and function graphs--the axes of which conventional mathematics treats in terms of consistent geometric and numeric coordinations. I consider these representations to be a part of a "hierarchical representational…

Master narratives frame students' historical knowledge, possibly hindering access to more historical representations. A detailed analysis of students' historical narratives about the origins of their own nation is presented in terms of four master narrative characteristics related to the historical subject, national identification, the…

This research investigated how teachers express links between ideas in speech, gestures, and other modalities in middle school mathematics instruction. We videotaped 18 lessons (3 from each of 6 teachers), and within each, we identified "linking episodes"--segments of discourse in which the teacher connected mathematical ideas. For each…

This study investigated analogical transfer of conceptual structure from a prior-knowledge domain to support learning in a new domain of mathematics: division by fractions. Before a procedural lesson on division by fractions, fifth and sixth graders practiced with a surface analogue (other operations on fractions) or a structural analogue (whole…

We examine how extended engagement in argumentation with peers leads to enhanced metalevel understanding of argumentive discourse. Following such engagement, young adolescents demonstrated enhanced understanding of counterargument and use of evidence as objectives of skilled argumentation, relative to a nonparticipating comparison group. Among the…

Previous research has demonstrated the effectiveness of particular instructional practices that support students' constructions of the partitive unit fraction scheme and measurement concepts for fractions. Another body of research has demonstrated the power of a particular mental operation--the splitting operation--in supporting students'…

Previous studies provided evidence of a relationship between mental rotation (MR) and motor processes in children and adults. However, there is no direct evidence that MR ability is a reliable predictor of success for motor performance. After completion of a MR test, the motor performance of 7- to 8-year-old and 11- to 12-year-old children was…

Argumentation is increasingly recognized as a fundamental intellectual skill, but evidence suggests that few adolescents or adults are skilled arguers. This article reports on an extended (3-year, twice weekly) intervention designed to afford dense practice in dialogic argumentation to middle-school students from traditionally academically…

Reasoning about mechanisms is one of the hallmarks of disciplined inquiry in science and engineering, but comparatively little is known about its precursors and development. Children at grades 2 and 5 predicted and explained the motion of simple mechanical systems composed entirely of visible linkages (levers). Students' explanations of device…

We illustrate a method, which is modeled on "breaching experiments," for studying tacit norms that govern classroom interaction around particular mathematical content. Specifically, this study explores norms that govern teachers' expectations for the doing of word problems in school algebra. Teacher study groups discussed representations of…

This article examines the pedagogical practices of two science inquiry teachers and their students using a Web-based system called Web of Inquiry (WOI). There is a need to build a collective repertoire of pedagogical practices that can assist elementary and middle school teachers as they support students to develop a complex model of inquiry based…

Using data collected in 125 seventh-grade and 56 eighth-grade Texas classrooms in the context of the "Scaling Up SimCalc" research project in 2005-07, we examined relationships between teachers' mathematics knowledge, teachers' classroom decision making, and student achievement outcomes on topics of rate, proportionality, and linear…

The examination of alternative hypotheses can initiate students into scientific practices and equip them with scientific literacy skills that will help them participate in ongoing debates involving complex socio-scientific problems. Hypothesis testing, in which the examination of alternative hypotheses is situated, has received much attention in…

Using the perspective of instructional conversation, we investigated how one teacher regulated student participation and conceptual reasoning in the middle-school mathematics classroom. We examined the elicitations--questions and provocative statements--made by the teacher over a four-day algebra lesson. Analyses showed how the teacher…

Instant-messaging software was used as a method to promote development of argumentation skills in middle schoolers. Transfer of skills across content domains was the major question investigated. Forty sixth graders engaged in electronic dialogues with peers on a controversial topic--for half a science topic (dinosaur extinction) and for half a…