Learning to justify scientifically by studying the origin of living beings Aprender a justificar científicamente a partir del estudio del origen de los seres vivos

This paper presents an investigation on learning science through writing justificative texts about the origin of living beings with students aged 14. In order to encourage students to write better justificative texts in the science class, first, we analyzed the role of learning scientific concepts (thematic pattern) and justificative texts (structural pattern) in an integrated way and, second, the influence of peer assessment activities in this learning process. The results show that students write better justificative texts after working simultaneously the structural and thematic patterns, improving both their structure and their understanding of scientific concepts. In addition, the peer assessment activities have been effective: the number of students admitting the possibility of spontaneous generation or giving no reasons for their point of view before the assessment activities is reduced to a half after the peer assessment.