This study focuses on the everyday operation of primary schools in Czechoslovakia during the so-called Prague Spring and the subsequent communist political clampdown after the invasion by the Warsaw Pact forces. The authors focus primarily on the experiences of teachers, how events in this complex period affected their professional lives, and how the renewal of totalitarian power was reflected in their work. The research is based on oral history as a method which enabled us to acquire unique knowledge concerning the work and life of teachers in the period under study. Findings from extensive archival research are also an important part of the research. These show that during the Prague Spring, as in Czechoslovak society as a whole, the socio-political climate in primary schools relaxed and communist power weakened, as reflected both in school operation and in-class instruction. After the Warsaw Pact invasion in August 1968, the regime became stricter again in schools and elsewhere (similar to before the onset of the Prague Spring). This was manifested especially in the constant control of teachers' activities during the Prague Spring, in their persecution, and through the increasing emphasis on ideological aspects of teacher training and pupil formation through instruction.