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…

Short term memory is famously limited in capacity to Miller's (1956) magic number 7 plus or minus 2--or, in many more recent studies, about 4 plus or minus 1 "chunks" of information. But the definition of "chunk" in this context has never been clear, referring only to a set of items that are treated collectively as a single unit. We propose a new…

Four experiments investigate the influence of topic status and givenness on how speakers and writers structure sentences. The results of these experiments show that when a referent is previously given, it is more likely to be produced early in both sentences and word lists, confirming prior work showing that givenness increases the accessibility…

Gutierrez (2006) experimentally demonstrated the effects of joint control and particularly the role of response mediation in the sequencing behavior of adults using an unfamiliar language. The purpose of the current study was to replicate and extend the procedures used by Gutierrez by comparing the effects of joint control training with the…

We describe a laboratory exercise developed for the cell and molecular biology quarter of a year-long majors' undergraduate introductory biology sequence. In an analysis of salmon samples collected by students in their local stores and restaurants, DNA sequencing and phylogenetic analysis were used to detect market substitution of Atlantic salmon…

Allowing students to create their own investigations and experiments to test hypotheses and answer essential questions is crucial to actively involving students in learning. It also provides them with opportunities to develop critical thinking and process skills. In this article, the authors explore a process called "BIDDI" ("Brainstorm,…

This study examines the effect of communication strategy instruction on EFL students' oral communicative ability and their strategic competence. In a 14-week English as a Foreign Language (EFL) course (English Use II) based on Communicative Language Teaching approach, 80 learners were divided into two groups. The strategy training group (n = 44)…

Designing inquiry-based science lessons can be a challenge for secondary school teachers. In this study we evaluated the development of in-service teachers' lesson plans as they took part in a 10-month professional development course in Peru which engaged teachers in the design of inquiry-based lessons. At the beginning, most teachers designed…

The literature seems limited in what is known about conceptual processes that underlie evolution of students with learning disabilities (SLD) conceptions of fractions. This exploratory study examines how a foundational scheme of unit fractions (1/n) may evolve through the mathematical activity of two fifth grade girls. We analyze data segments…

It is a hard task to strike a balance between extents of control a learner exercises and the amount of guidance, active or passive, afforded by the learning environment to guide, support, and motivate the learner. Adaptive systems strive to find the right balance in a spectrum that spans between self-control and system-guidance. They also concern…

Incorporating scientific fundamentals via engineering through a design-based methodology has proven to be highly effective for STEM education. Engineering design can be instantiated for learning as they involve mental and physical stimulation and develop practical skills especially in solving problems. Lego bricks, as a set of toys based on design…

First-generation college students (students for whom neither parent has a 4-year college degree) earn lower grades and worry more about whether they belong in college, compared with continuing-generation students (who have at least 1 parent with a 4-year college degree). We conducted a longitudinal follow-up of participants from a study in which a…

In 1990, a woman was wrongly convicted of poisoning her infant son and was sentenced to life in prison. Her conviction was based on laboratory work that wrongly identified ethylene glycol as present in her son's blood and in the formula he drank prior to his death. The actual cause of the infant's death, a metabolic disease, was eventually…

Much of our understanding of metabolic pathways has resulted from the use of chemical and isotopic labels. In this experiment, a heavy isotope of carbon, [superscript 13]C, is used to label the product of the well-known RuBisCO enzymatic reaction. This is a key reaction in photosynthesis that converts inorganic carbon to organic carbon; a process…

This exercise provides students hands-on experience with the topics of glycosidation, hemiacetal and acetal formation, proton nuclear magnetic resonance ([superscript 1]H NMR) spectroscopy, and kinetic and thermodynamic product formation. In this laboratory experiment, the methyl acetal of ribose is synthesized, and the kinetic and thermodynamic…