water boiling in a beaker and the ‘motivating force’ that produces this movement, that
is the movement of the ‘particles’.
The students interpreted the resources of movement in the ‘Hide Particles’ view as a
sign of change and transformation. In the ‘View Particles’ option the students read
the resources of movement more literally: they describe the movement of the
‘particles’ quite literally, without interpreting it as a sign - that is they describe the
signifier without being able to link it with what it is that it signifies. In the case of the
transformation of a gas to a liquid, for instance, several students describe the
‘particles’ as ‘moving up’ or ‘coming down’ and describe the change in speed and
direction of the ‘particles’. However, they did not link these signifiers of movement
to the transformation of a gas to a liquid. Their ability to ‘read’ the signs of
movement is restricted by their understanding of the theoretical entities that the signs
relate to. The students appear to read the resources of movement in relation to the
specific ‘states of matter’ - that is to identify the movement of ‘particles’ in a solid, a
liquid or a gas, rather than to read them as signs of a process.
Although the students comment on the movement of the ‘particles’ in the
investigations that they observe on the CD-ROM the terminology that they use varies
considerably. I want to suggest that their comments can be read as a sign of their
ability to interpret the movement as scientifically meaningful. For instance, one of the
students, Lucy, considered to be particularly good at science described the movement
of the ‘particles’ in ‘scientific- technical’ terms such as ‘moving freely’, ‘restricted
movement’, ‘move faster’ and ‘move slower’. Another student, Kylie, used terms
such as ‘come out quick’, ‘move just a bit (not even an inch)’, ‘move much more than
before’, ‘move a bit not much’, and ‘the particles hardly move a bit’. I want to
suggest that the students’ ability to ‘strip away’ the everyday to reveal what is
Criterial to school science is at play in their potential to interpret the movement of the
‘particles’ as meaningful. Although both of these kinds of working might be thought
of as being ‘theoretically the same’ the theoretical and epistemological force that
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