Undergraduate and masters students' understanding about properties of air and the forms of reasoning used to explain air phenomena

Although air is all around us and is an essential part of our everyday environment, its properties are taken for granted and not consciously considered by children. The nature of air is very difficult to teach because air is colorless, odorless, and tasteless. Although children are familiar with the word “air,” stationary air has little reality for them. Research studies on children’s preconceptions about air (Piaget, 1972; Sere, 1982; Driver, 1983; Driver, Leach, Scott & Wood-Robinson. 1994; Borghi, Ambrosis, Massara, Grossi & Zoppi, 1988; Tytler, 1998) revealed many widely shared interpretations and explanations of phenomena and events that differ from accepted scientific explanations and sometimes become a barrier to acquiring the correct body of knowledge (Arnaudin & Mintez, 1985). Bulunuz, Jarrett, and Bulunuz (2009) found that middle school students have misconceptions about the physical properties of air. According to Wandersee, Mintzes, and Novac (1994), teachers may hold some of the same misconceptions as the children. Hashweh (1987) found that teachers’ subject matter content knowledge affected their planning by embedding their misconceptions in their teaching and resulted in passing the misconceptions on to the students.

In the literature, there is a body of research on preservice and inservice teachers’ misconceptions. These research studies include all aspects of science, concerning earth and space (Mant & Summers, 1993; Dal, 2009; Bulunuz & Jarrett, in press), physical sciences (Galili & Hazan, 2000; Halim & Mohd, 2002; Jarvis, Rell, & McKeon, 2003; Bayraktar, 2009), and biology and environmental phenomena (Khalid, 2003; Çibik, Diken & Darçin, 2008). However, in an extensive literature review, only one study was found that investigated the forms of reasoning preservice teachers used to explain air pressure phenomena (Leite & Afonso, 2004). In addition to air pressure phenomena, the present study explores preservice teachers’ conceptions and the forms of reasoning they used to explain the following phenomena: (a) Bernoulli's Principle, i.e., flowing air exerts less pressure than stationary air; (b) the absence of air and its pressure on the Moon and in outer space; (c) the existence of lower air pressure at higher altitudes; d) the effects of air pressure on the boiling point of water; e) the effects of heating on the density of air; and (f) the pushing force of air pressure as the cause of what is commonly called sucking.

Research on Reasoning about Scientific Phenomena
Driver, Leach, Millar, and Scott (1996) explored the forms of reasoning used by students (9-16 years old) to explain various phenomena and developed a framework that included three main categories: (a) phenomena-based reasoning (PBR), description rather than explanation; (b) relation-based reasoning (RBR), incomplete attempt to explain; and (c) model-based reasoning (MBR), where explanations are based on conjectured models that have to be evaluated against empirical evidence. Only MBR reflects a comprehensive explanation. Driver et al. found that 9-year-olds typically used phenomena-based reasoning, 12- and 16-year-olds typically used relation-based reasoning, and only the oldest students employed much model-based reasoning. As pointed out by Leite and Afonso (2004), model-based reasoning can be either correct or incorrect from the standpoint of the science involved, since the reasoning can be based on alternative conceptions of science.

Leite and Afonso (2004) used Driver et al.’s (1996) three types of reasoning to categorize understanding about air pressure among 38 Portuguese preservice teachers. These preservice teachers had finished all their science coursework and were preparing for student teaching in the physical sciences. Leite and Afonso found that approximately 50% of their subjects used model-based reasoning to predict or explain a balloon and bottle experiment, 16% used such reasoning for a burning candle in a jar experiment, and only one person could explain an egg in bottle experiment using model-based reasoning. The dominant form of reasoning was relation-based. Leite and Afonso concluded that their subjects had difficulty relating evidence and theory and that the ability to use model-based reasoning is important for teachers who need to be able to help their students interpret physical phenomena in light of scientific theory.

Hands-on Activities and Discrepant Event Demonstrations as Conceptual Change Strategies
The need to build conceptual understanding on experience is central to the constructivist philosophy of Piaget, Vygotsky, and Dewey. Real experiences allow people to construct their own understandings in a meaningful way (Piaget, 1968; Vygotsky, 1978; Dewey, 1910/1997). The common premise for these theorists is that learning is an active process requiring physical and intellectual engagement with the learning task. Piaget (1973, p. 36) states, "Understanding always means inventing or reinventing, and every time the teacher gives a lesson instead of making the child act, he prevents the child from reinventing the answer.” Demonstrations and hands-on activities create “external intrusion” (Piaget, 1968, p. 113) into current thinking and stimulates equilibration, leading to conceptual change.

According to Piaget (1973), a state of perplexity and doubt (a state he called disequilibrium) is a necessary first step in learning. According to his theory, learning takes place at all ages, as people try to equilibrate (make sense of) dissonant experiences through the processes of assimilation and accommodation. Similarly, the Theory of Cognitive Dissonance by Festinger (1957) proposes that dissonance, being psychologically uncomfortable, will motivate the person to try to reduce the dissonance. Events that do not fit one’s existing understanding of events, discrepant events, function by causing dissonance between what is physically observed to occur and what one thinks should occur. Since it is impossible to change what is physically observed to have occurred, the only alternative is to begin seeking information that logically explains the occurrence. In research with primary trainee teachers, Joan (2006) found cognitive conflict useful as a strategy for promoting conceptual change and pedagogical insight about light and shadows.

Considerable research using hands-on activities for promoting conceptual understanding has been conducted on various topics with preservice teachers (Kelly, 2000; Gibson, Bernhard, Kropf, Ramirez, & Van Strat, 2001) and inservice teachers (Bulunuz & Jarrett, in press; Ebert & Elliot, 2002). According to these studies, hands-on activities and demonstrations improved conceptual understanding of various science concepts. The present study explores the impact of various hands-on activities and discrepant event demonstrations on preservice and inservice elementary teachers’ conceptual understanding about properties of air.