Students’ language use when talking about the evolution of life - negotiating the meaning of key terms and their semantic relationships

In this paper, we explore an idea from Vygotsky about the meaning and sense of words, and how it manifests itself in students’ talk. This is done by analysing the discussions of 15-year old Swedish students participating in teaching activities concerning biological evolution. It turned out that the students seldom articulated the scientific terms. Instead, they contextualised by using three strategies – paralleling, transferring, and delimiting. All three of these strategies have merits and drawbacks in connection with ‘meaning’ of single terms. However, when combining the terms into thematic patterns, the students formed rather sound and coherent scientific explanations. This is understood as relying on the students’ use of an interlanguage where colloquial expressions serve as an asset in sense-making. The verbalisation of an explanation in an interlanguage is advantageous when communicating in social life outside the science classroom, and thus the possibility of further sense making is enhanced