the pre-survey to the post-survey and again by the time of the post-post-survey. For
example, after the intervention, one pupil said that models were ‘to see things
smaller so we can see what they look like’. This is similar to Smit and Finegold’s
(1995) finding that secondary student teachers in Namibia and South Africa
thought that the main use of models was as scale representations of reality so
teachers could explain science ideas more clearly.
The second most popular view of models in the post-post-survey was their use
to ‘show and test new theories’. One pupil, for example, said in the post-survey that
models were ‘to calculate new theories’. Support for this view is surprisingly small
considering that the pupils had repeatedly used a model (the orrery) during the
intervention to test theories that were new to them. The authors note the
significance of this comment, however, because this higher level of thinking is the
ultimate aim of how we hope pupils will use models.
The idea that models can be used to find out things had little support from
these pupils, despite the fact that they had been finding out astronomy ideas by
using a model (the orrery) during the intervention. For example, Jennie referred to
models being used to investigate unknown aspects, noting that scientists would use
models to ‘see what changes, and if anything drastic happens they will know’.
Confusion between models and instruments, evident in that support for the
view that models can be used to look at things, increased over the three surveys.
In summary, the astronomy intervention helped to develop Year 7–8 pupils’
understanding about the role of models in science, although many of them
continued to view models as being scaled versions of the reality they represent.
Other traditional astronomy knowledge: learning outcomes
The pupils’ other traditional astronomy knowledge of the solar system was
investigated by the surveys. Table 6 shows the percentages of the class who correctly
selected the scientists’ responses in the pre-, post- and post-post-surveys. It
indicates that, as a result of the intervention, these Year 7–8 pupils did acquire and
retain adequate traditional astronomy knowledge with respect to the order of the
planets out from the Sun, descriptions of the planets, relative sizes of the planets,
solar eclipses, the Moon as the main cause of tides on Earth and that we can
sometimes see the Moon during the day. Further discussion of these results, and
comparison with other findings, is reported in Taylor (2000).
A further conclusion from table 6 is that understanding about the Moon
remained difficult for these pupils despite the intervention. For example, most of
them remained convinced after the intervention that the Moon is predominantly a
nighttime phenomenon, despite having observed it during the day and despite
having engaged in a lengthy discussion on that topic in lesson 7 of the
intervention.
Discussion
Pupils’ responses to mental model building
The efficacy claimed for this approach rests on the teacher interviews and lesson
transcripts, which revealed that the pupils responded positively to the learning–
teaching approach adopted in this astronomy intervention. They showed a clear