Secondary school polyhedrons with internet

The thesis is destined mainly for high school teachers and students of descriptive geometry. Above all it deals with the intersection and the construction of pyramids and prisms in projections. Students can meet with these phenomena at high schools during lessons of descriptive geometry. The constructions of the intersections of figures are demonstrated on solved tasks. The tasks are processed in graphic programmes GeoGebra and Cabri 3D prospering from the following advantages and facilities of these programmes: a stepping of the construction, a contour accentuation or a secretion of auxiliary lines etc. Besides these solved tasks, there are also some unsolved tasks for practice at the ends of chapters. The introductory chapter contains definitions and characters of common polyhedrons and regular (Platonic) figures. The thesis consists of web sites, a printed version and an enclosed printed version in .pdf format