This paper continues earlier studies about the teaching and learning of the arithmetic average and it is part of a broader research in progress at Santiago of Compostela University (Spain). We have analyzed a sample of six teaching manuals (textbooks) used for teaching mathematics at high schools in Salvador, Bahia. The study is based on theoretical ideas by Godino and Batanero (1994; 1998) and Godino and Recio (1997) who propose a semiotics perspective based on the functions of signs by Hjelmslev (1943), later known as "semiotic function".( Eco, 1979).
- Prof Dev