A Common Core to Chemical Conceptions: Learners’ Conceptions of Chemical Stability, Change and Bonding

Abstract

12 In addition, progress variables mediate between core ideas and specifi c concepts and skills being learned and serve as a means for monitoring student understanding during instruction (Wilson 2005 , 2009). Once developed, progress variables can be used to provide information to both teachers and students about student develop-ment during instruction (Kennedy et al. 2006 ; Wilson 2005 , 2009). Thus, learning progressions and progress variables could be powerful tools for promoting students' understanding of subject matter. In their review of research on students' understanding of the particle model, Harrison and Treagust (2002) found that traditional curriculum materials present the particle nature of matter as a topic, focusing on the history of the atom. At the middle school level (ages 11–14) in the United States, students are often taught through direct instruction the structure of the atom and that the different states of matter are related to the movement and arrangement of atoms (American Association for the Advancement of Science [AAAS] 1993). This direct instruction assumes that once presented with the particle model, students will accept it as the correct model. For example, at the high school level (ages 14–18), a textbook presents the history the atom beginning with the Greek philosophers and ending with the current quantum model of the atom (Davis et al. 2006). Moreover, research shows that students fi nd it diffi cult to learn the particle model using traditional curriculum materials because they present particle concepts to stu-dents without helping them to develop these concepts, to take into account their prior knowledge, or to use them as models for explaining phenomena (Harrison and Treagust 2002 ; Krajcik 1991 ; Nakhleh 1992 ; Stevens et al. 2010). Often, students do not develop appropriate ideas because they never apply and reapply these ideas to explain phenomena. In this chapter, we describe a progress variable for the par-ticle model of matter, evidence for this progression, and the importance of building students' ideas over time through key instructional experiences. The particle nature of matter is a fundamental concept for learning and understand-ing many physical and chemical processes. Novick and Nussbaum (1978) studied students' ideas about the particle nature of matter as it relates to gases and found that students did not (1) internalize ideas related to the vacuum concept (empty space) and (2) understand the intrinsic motion of particles or the interaction between particles during a chemical change. Other studies have shown that students assign macroscopic properties of substances to the atoms/molecules that compose the sub-stance (Ben-Zvi et al. 1986 ; Lee et al. 1993 ; Nakhleh 1992). Moreover, learners and many adults hold nonnormative science ideas regarding the structure of matter and how to explain phenomena. Our position is that student's prior knowledge of matter needs to be used as a resource to build understanding. The nonnormative science ideas that students possess have been documented (Driver et al. 1985 , 1994). For example, students misconstrue mass and size of an