The one-year PGCE is too short because scientists usually have to teach their degree subject and the other two sciences. This reduces confidence and causes some to avoid teaching the subject they know least about, researchers at London Metropolitan university found.
Concerns about science teaching by non-specialists have been voiced for many years. But the study by Sarah Smart and Merryn Hutchings points out that it is teachers and pupils in the most disadvantaged areas who suffer most from this problem.
They interviewed 25 newly-qualified science teachers in 22 secondary schools and found all were teaching outside their specialist area for part of the week. In selective and independent schools, the teachers taught a second science for only a period a week - so they could gain wider experience. However, teachers in the most challenging inner-city schools were more likely to find themselves teaching combined science. Much of their week was therefore spent teaching outside their specialism. "The teachers we interviewed had not all understood that a PGCE in a named science prepares teachers to teach across the science curriculum, or that they would be expected to teach outside their specialism both during training and when they got jobs," the researchers told the conference.
A few teachers said they preferred to teach a science discipline they had not studied at university as it helped them to see the subject from the student's perspective. But most felt less effective when doing so.
They had more difficulty explaining concepts, were sometimes unable to answer pupils' questions and had to rely heavily on worksheets. One biology specialist admitted she had arranged to swap classes with a physicist, without the knowledge of her head of department, so that pupils would not "lose out".
The researchers were also disturbed to find that in almost every school the heads of department had opted for teaching arrangements that were simply "a pragmatic response to circumstances".
Teacher shortages, challenging pupils, and the need to maximise attainment were cited, rather than a belief that science should be taught as a unified method, or that it was important to introduce pupils to the different science disciplines.
The researchers say that departments could do more to help newly-qualified science teachers but they also recommend more training before and after they enter the profession.
"The first year of a two-year PGCE science course could be entirely devoted to increasing subject knowledge and those who already have appropriate knowledge could be exempted from that first year," they suggested. "But meanwhile, perhaps the most important step would be to have structured in-service training for science teachers in the early stages of their careers."