Kécia Gomes de Moura, KéciaAna Emilia de Melo Queiroz, Ana EmiliaAlex Sandro Gomes, AlexMaurício da Motta Braga, Maurício2026-10-162026-10-162011-07-30https://repositorio.univasf.edu.br/handle/123456789/1558The software is grounded in Gérard Vergnaud's Theory of Conceptual Fields, which proposes representing problem situations through diagrams specific to each category of mathematical structure. It covers six categories of problem situations: Composition, Transformation, and Comparison of Measures (additive structures), and Multiplication, Division by Parts, and Division by Shares (multiplicative structures). For each one, the interface presents a word problem and guides the user toward identifying the correct category and building the corresponding diagram through direct manipulation (drag and drop) of the problem's numerical elements. The software provides constant feedback on the user's actions, with error messages specific to each type of mistake (incorrect categorization, incorrect positioning, incorrect sign, or incorrect calculation), along with on-demand help features ("what's the next step?" and "more hints"), undo/redo, and task restart. For registered users (via login and password), the system also saves and retrieves the resolution state, allows editing of registration data, and displays a detailed history of attempts, errors, and steps taken. GERARD was implemented in the Java language, using the Java2D API (for drawing the diagrams and the drag-and-drop effect) and Java Swing (for the graphical interface components), having been developed both as a desktop application and as a Java applet. The system was modeled in UML with the help of Astah Community, in the NetBeans development environment; the database, used for authentication, history, and state persistence, was modeled with ERwin and implemented in SQLite. The architecture follows the MVC (Model-View-Controller), Decorator (for the dynamic composition of the diagram drawings), and State (for switching between the software's four configurations — additive and multiplicative structures, for guest and registered users) design patterns. Validation involved testing with five teachers from the M. Mª José Lima da Rocha school (Juazeiro, BA), which allowed usability contingencies to be identified and corrected before final release. GERARD is intended, above all, for the continuing education of elementary school teachers, offering them a tool that highlights the diversity of reasoning required by seemingly similar problems, expanding their ability to propose varied problem situations in the classroom. Having been designed as both a desktop application and an applet, the software also paves the way for its use in distance education programs, expanding the reach of teacher training to educators in municipalities far from major urban centers — a relevant reality in the state of Bahia.https://creativecommons.org/licenses/by-nc/4.0/Engenharia de SoftwareSoftware EducativoTeoria dos Campos ConceituaisRaciocínio MatemáticoOutroCIENCIAS EXATAS E DA TERRA