This article discusses the function of a particular feature of sign language--mouth action--as it is expressed in various discourse contexts. Specifically, we examine forms of mouthing and mouth gesture as they are used in signed narrative and expository texts, highlighting the signers' choices during the production of these two text types. We…

One of the challenges of understanding the complexity of so-called reform mathematics instruction lies in the observational tools used to capture it. This article introduces a unique tool, drawing from commognitive theory, for describing classroom discussions. The Realization Tree Assessment tool provides an image of a classroom discussion,…