LOGO and Elementary Mathematics Education in Portugal appreciation because they are in constant evolution and facilitate work. This work is usually relevant to the subjects and to their community. According to Papert (1980), more important than absorbing mathematical knowledge developed by others as prerequisite to practice math, is math practice as a prerequisite for learning mathematics. The big change advocated for school mathematics, to become appropriable, involves the verification of three principles: 1. Principle of continuity: mathematics must have a relationship of continuity with the knowledge and experience of each individual, allowing him/her to establish a feeling of affection; Principle of Power: mathematics should empower children to develop proj- ects that match their needs and their interests, and that may not be achieved without it; Principle of cultural resonance: mathematical content must make sense in a wider social context. 2. 3. The LOGO Language: A Point of Departure The LOGO programming language allows the execution of instructions that can be classified in two types: the primitives and the procedures. The primitive instructions are based on primitive language of Logo (a language that all "turtles" know). The procedures are sets of instructions containing primitives and/or other procedures to which we attach a label. These new words will become part of the "dictionary" of the turtle. In working with Logo one has to consider two points: Programming itself and the implementation of programming. These two moments can happen immediately one after the other following the order indicated above, or we can choose to "save" the procedures established, to implement them later. This option allows articulating several procedures. The in- structions given to the turtle may be entered in the inbox and executed one by one, or all at once, as we want a more or less immediate feedback on our programming. At the elementary level, several packages available allow children to produce static and dynamic graphics, to develop numerical investigations etc. FIRST PART: A CASE STUDY ON THE APPLICATION OF LOGO IN ELEMENTARY SCHOOL The case below is part of the practical component of the dissertation for a Master's degree in Child Studies - Teaching and Learning of Mathematics run by the Uni- versity of Minho. 493