Web textbook for descriptive geometry

In this paper we present educational material which is a basis for a web textbook designed for the lectures on geometric subjects, [1]. The authors of the textbook are geometry teachers from the University of Zagreb, three of them, Sonja Gorjanc, Helena Koncul and Iva Kodrnja, coming from the Faculty of Civil Engineering, and one, Ema Jurkin, from the Faculty of Mining, Geology and Petroleum Engineering. The contents of the textbook cover the topics that are taught within the courses Descriptive Geometry and Perspective at the Faculty of Civil Engineering, and courses Descriptive Geometry and Descriptive Geometry with Computer Graphics at the Faculty of Mining, Geology and Petroleum Engineering, however, some of its content is also applicable to other faculties in Croatia. The textbook is available online for free and licensed under CC BY-NC-SA 4.0 licence. One can include the full textbook, or only the parts of the textbook, into various e-learning platforms. Materials can be used free under the same conditions, i.e. must not be used commercially. The importance of clear and careful spatial reaso– ning and its graphic representation in the education of future engineers makes descriptive geometry a tradit– ional mathematical course at technical faculties, parti– cularly at those related to civil engineering. A series of high-quality descriptive geometry textbooks were published in Croatian during last fifty years, and this textbook presents their sequel. However, it really differs from previous textbooks in the application of infor– mation technologies in presenting classic contents and introducing 3D modelling in descriptive geometry teaching. Therefore, a different approach to some course units has been required. Due to specific characteristics of descriptive geometry as a discipline of mathematics, the textbook is graphically rich and it contains 38 interactive files, 493 original drawings and figures, 83 original animations, 82 original presentations and 93 video clips (up to five minutes), a total of more than six hours of audio and video material. It took quite a long time to prepare this extensive teaching material, which required interdisciplinary knowledge and skills, in parallel with lesson prepa– ration. The starting point of the textbook was repository of educational materials created within the project Introducing 3D Modeling into Geometry Education at Technical Colleges that was supported by Fund for Development of the University of Zagreb, [2]. During the year 2012 twelve teachers worked on the project, and four faculties were involved. The head of the pro– ject was Sonja Gorjanc. The main goals of the project were strengthening the professional and scientific colla– boration among teachers, developing teaching metho– dology for 3D computer modeling to enhance geometry courses, and harmonization of educational material sta– ndards and their implementation in the e-learning sys– tems of the technical faculties that were involved. The focus of the project was creating a basic repository of material related to common teaching topics and those customized to profiles of each faculty, [3]. The expe– rience of teachers using created educational materials were described in [4]. During the last few years we enriched the existing repository with new material and increased the number of topics it used to cover, giving it a form of textbook. We tried to connect the benefits of classical and modern approaches to teaching geometry guided by the thoughts presented in [5], as well as in [6] and [7].