The main reason for carrying out the STARS project was that in the 21st century, it is essential to improve scientific and technical skills and strengthen competitiveness in Europe, which can only be achieved if the country has a sufficiently educated population. According to surveys, primary school pupils are insufficiently educated in science subjects, they lack interdisciplinary skills. In order to acquire relevant knowledge, it is very important that they learn in a conceptual structure, make observations, cooperate and make the most of current technological progress. At the same time, astronomy is included in science education only very marginally, and teachers often do not have sufficient knowledge, skills and methods to teach astronomy in an innovative way.For this reason, EXPOL PEDAGOGIKA s.r.o., the publishing house of textbooks for primary and secondary schools, has started to implement the international project STARS (Successfully Teaching AstRonomy in Schools) since 1 November 2017, the main goal of which is to support primary school teachers in teaching astronomy.The project brought together 7 organisations from Slovakia, the Czech Republic and Bulgaria, namely 3 schools, 1 renowned university, 1 non-governmental organisation focused on astronomy, a company creating innovative digital solutions in the school sector and a leading publisher of professional literature.The project focused on:•equipping teachers teaching at lower secondary education with innovative methods, knowledge, competencies and tools for teaching astronomy within the curriculum,•creating a training program for teaching astronomy, as ready to use educational tool for teacher training providers (e. g. universities, continuing education providers, observatories, astronomical associations, but also as a tool of self-development for individual use, etc.),• creating a concept of a new educational program for teaching astronomy, which reflects current trends and attitudes of pupils towards the modern teaching process,• supporting critical thinking, analytical and abstract perception in order to increase the level of knowledge acquisition by pupils, as well as the acquisition of relevant knowledge,•equipping the target groups of the project with freely available, language-relevant and high-quality educational resources for teaching astronomy.More than 3600 primary school pupils, science teachers, people involved in education, policy makers, academics and parents participated in various project activities: in the creation of outputs, their testing, validation, demonstration during workshops, targeted dissemination and their use in practice. The project lasted 34 months and further dissemination activities after its completion will ensure its sustainability.As part of the project, we implemented the following activities and outputs:- we designed, developed, tested and validated: STARS Methodical Handbook for Teachers: a handbook for lower secondary teachers teaching subjects involving astronomy; STARS Training Program for Teachers: offers an innovative and comprehensive approach to improving teachers' practical skills and providing them with further in-service training;-we designed, created, tested and launched the STARS Online Platform, which contains created outputs in digital form, which will enable the use and sustainability of project outputs in the future;-we created the STARS Concept for Astronomy Education Program, which provides ideas on how astronomical topics can be presented in a better way in terms of curriculum to pupils in the higher classes of primary schools;-we organised an online STARS dissemination conference for local and foreign participants, where we presented the outputs to the general public.All outputs are in 4 language versions – Slovak, Czech, Bulgarian and English.TARGET GROUPS: Teachers:- improving the knowledge, skills and competences of learning subjects related to astronomy,- increasing the capacity to offer interactive teaching methods and skills to motivate students to take an interest in science and especially astronomy.Pupils:- an inspiration to pursue the studies of astronomy in the future, - expanding the competencies of critical thinking and motivation to actively participate in the teaching process,- gaining relevant knowledge of astronomy.Politically active persons:- improving the ability to make decisions based on real needs and innovating curricula and curricula to meet the needs of modern societyOTHER STAKEHOLDERS:- gaining awareness of the close relationship between science and other basic skills,- directors: supporting and creating an environment for education in astronomy,- parents: supporting the child's interest in astronomy.PROJECT PARTNERS:- improving the capacity to cooperate at transnational level,- strengthening the reputation of the education sector through the creation of freely available innovative materials and platforms.