# CRDM-Guy BrousseauLines of research

During the 28 years of operation of COREM, lines of research evolved as far as the Theory of Didactical Situations was developed.

At a first instance, lines in

Later, after interaction with research in didactics engineering on new subjects, a second axis was developed: a more general study of didactical situations in mathematics, yielding new theoretical concepts such as

At a first instance, lines in

*didactics engineering*about situations of didactical use (linked to mathematical subjects of the precdeding section), has allowed for the elaboration of teaching processes related to the basic notions of the curriculum of the elementary school and have driven to the explicit form of so important concepts such as*fundamental situation*,*didactical variable*or*environment*.Later, after interaction with research in didactics engineering on new subjects, a second axis was developed: a more general study of didactical situations in mathematics, yielding new theoretical concepts such as

*didactical obstacle*,*didactical contract*,*institutionalization*,*didactical memory*,*didactical transposition*, or*structuration of the didactical environment*, etc.