Does the material involve students in considering whether the argument and evidence support the particle model of matter?
Students are not consistently given opportunities to consider the argument made in favor of the particle model of matter. After they engage in Explorations 1 and 2, they are asked to summarize their individual cases for or against the existence of particles; evaluate hypothetical, student-built cases for the existence of particles; revise their cases; and convey their cases to the class (Level Blue, p. 91s). However, they are not offered any opportunities to evaluate alternative models that could account for the observations in Explorations 1 and 2. After presenting an account of some of John Dalton’s observations and inferences about the particle model (pp. 92–93s), the text informs students that “you have developed a model of the structure of matter” (p. 103s) and then makes three assertions about the particle model. Thus, at least up to this point in the text, the particle model has been “legislated” as the accepted model. The case-building that might support this notion is neither
