Many studies have shown that students of all school levels hold alternative conceptions that differ from the scientific conceptions transmitted by the school. These results raise some questions about the efficacy of traditional teaching and stress the need for using teaching strategies that explicitly take into account the alternative conceptions that students bring to the science classes.

This issue has recently been raised and widely discussed throughout Portugal and the proposals for the new science syllabuses advise teachers to take it into account. However, the number of studies investigating both the teachers' attitudes towards this issue and the use of teaching strategies based on students' alternative conceptions is very limited.

This article aims to present the results obtained from science teachers about their attitudes towards students' alternative conceptions and the use of teaching strategies based on these conceptions.

The results may contribute to the planning of in-service courses.