Promoting the principles of sustainable development in the educational process is necessary for the students' ecological thinking development. Considering that the main role model for the pupils is the teacher, encouraging students' environmental thinking in the wake of creativity, specially future teachers' thinking is important for the encouragement of pupils' environmental thinking. The aim of the research is to recognize the level of the creative product and to recognize the principles of sustainable development in students of teacher education. A mixed methodology was used. In order to collect quantitative dana, a scale of attitudes towards the environment and a scale of the level of use of didactic unformatted materials were used. In order to collect qualitative data, student works were analyzed using the TCT-DP construct and students were asked open-ended questions. As the main advantages of creative design with didacticaly unformed materials in relation to classical art techniques and materials, the students pointed out: providing greater freedom in creative expression, the absence of certain patterns and encouraging greater imagination. The results of the research show that the respondents most often made decorations on their own and made sketches and paintings. Also, the analysis of the works shows that the free choice of materials in the design enabled a greater development of creativity. Isolation due to the COVID-19 pandemic didn't prevent most students from using accessing didactically unformed material. The students showed that they mostly advocate the view that environmental protection benefits everyone. They mostly showed their knowledge of the concept of didactically unformed material, which enables various creative games of building, combining and varying in the artistic meaning. In the end, they agreed on the claim that the use of didactically unformed material develops students' knowledge of sustainability.