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came to class with existing alternative notions of the topics to be studied and (b)
that often students who failed to acquire target knowledge did learn from their sci-
ence classes, but developed understanding inconsistent with what the teacher was
attempting to teach (Driver & Erickson, 1983; Gilbert &Watts, 1983). A very active
research programme developed which explored the nature of the students' ideas
presented before, during and after teaching, and which was concerned with how
conceptual change occurred and what kind of teaching best facilitated the desired
shifts in student thinking (Taber, 2009).
Examples of Students' Ideas
The literature describing learners' ideas in science (reported as “misconceptions”,
“naive physics”, “intuitive theories”, “alternative conceptions”, “alternative frame-
works”, etc.) is vast, so for readers not familiar with this research I offer a few
examples of the kinds of ideas that have been found to be common among learners.
One of the most well-established examples that has been widely reported con-
cerns how people (not just children) understand the relationship of force and motion.
According to physics, an object will remain in its state of motion unless acted upon
by a force. So an object moving in a straight line continues to do so at the same
velocity unless subjected to a force. Although this idea is well established in science
(since Newton) it is at odds with what most people expect. Students are commonly
found to consider that an object will only remain moving if a force is continuously
applied in the direction of motion (Taber, 2009, pp. 223-224).
Another example concerns the growth of plants. It is commonly considered that
the material in a plant, for example a tree, is incorporated into the tissues after
being extracted from the soil through the roots. Whilst this is not entirely contrary
to scientific thinking—minerals are accessed in this way, and are incorporated into
tissue—it is inconsistent with the scientific model, where photosynthesis allows the
plant to acquire carbon that forms the basis of new tissue from the carbon dioxide
in the air (Taber, 2009, pp. 224-225).
Chemistry also offers many examples. So learners commonly consider
neutrali-
sation
(the type of reaction that occurs between an acid and a base) to be a process
that necessarily leads to
neutral
products (Schmidt, 1991). However, this is only the
case when the acid and base are of similar strength. If the weak acid ethanoic acid
reacts with the strong base sodium hydroxide, then the product, sodium ethanoate,
is not neutral but basic.
Learners also commonly suggest that the reason chemical reactions occur is
because the atoms in the chemicals “need” to obtain full electron shells, which
they do by interacting with other atoms to donate, share or acquire electrons (Taber,
1998). This notion is widespread despite most commonly studied reactions in school
science occurring between reactants where the atoms already “have” full electron
shells. The scientific explanations concern how the reactions involve interactions
between the charged particles in reactant molecules (or ions) that lead to new
