This master's thesis is mostly focused on the study of three-dimensional design in the teaching of Art and linearly thinned mass as an artistic concept presented in the objectives of elementary school Art curriculum. The theoretical part of the paper includes defining and explaining concepts related to three-dimensional design, such as space, volume, mass, and branches of the visual arts that operates in three dimensions, such as sculpture, architecture, urbanism, horticulture, with emphasis on linearly thinned mass. The linearly thinned mass is described in more detail, as well as the notion of line to which this type of mass is closely related. Theoretical part also includes the analysis of four 20th century and contemporary artists (Alexander Calder, Naum Gabo, Eva Hesse and Siniša Majkus) who use linearly thinned shapes in their works. The characteristics of three-dimensional shaping in the teaching of Art Culture are further described with regard to the subject curriculum and art techniques and materials with which we can create linearly thinned shapes. Although the linearly thinned shapes are often seen in the natural world, it was only until the artists of the 20th century, who were in search of new forms and materials, applied linearly thinned shapes in their works to a greater extent. For this reason, the theoretical part of the paper is dedicated to previously mentioned artists whose works of art have served as inspiration for the design of the practical part of the thesis. Therefore, the practical part includes a description of the realization process as well as the analysis of the final results of four art activities designed according to these works of art. These art activities explore the different ways in which the linear thinned mass could be utilized in the Art class.