The Teachers dataset is one of the outputs of the History+ project. The History+ project aimed to examine the potential for transforming the methods of teaching history at middle schools. The project was announced by the Ministry of Education, Youth and Sports in the form of a so-called experimental intervention. It focused on developing students' key competences, including critical thinking on history and research work with sources of historical information. At the same time, in connection with the 2030+ Strategy, the project verified a way of supporting schools in actually transforming their teaching methods and creating of a model for working with teachers. The History+ project was launched on 1 February 2021 in cooperation between the National Pedagogical Institute of the Czech Republic and the Institute for the Study of Totalitarian Regimes. The Teacher dataset results from pre-test and post-test measures, first in the 2021/2022 and second in the 2022/2023 academic year. Participating teachers and their coordinators, also active teachers, responded. The intervention was primarily concerned with contemporary history taught in middle school, so history teachers in the 9th grade of primary schools and corresponding grades of multi-year Gymnasiums were primarily recruited. However, the project also involved teachers of Gymnasiums and secondary vocational schools where modern history is also taught.