This paper aims to gain insight into language production and academic language of 4- and 5-year-old students and their teachers in the course of a teacher intervention during kindergarten science education. The study is based on videotaped classroom observations, and specifically focuses on the academic language use of students (N[subscript intervention] = 18, N[subscript controls] = 26) and teachers (N[subscript intervention] = 5, N[subscript controls] = 5). The results suggest that this general teacher intervention yields interesting changes in language use and production. Patterns of change over time confirm the idiosyncratic and non-linear nature of these changes. Science lessons represent an appropriate context in which to acquaint students with academic language, which can be used as a basis to build upon more sophisticated language skills.