Content and language integrated learning (CLIL) represents an increasingly popular approach to bilingual education in Europe. In this article, we describe and discuss a project which, in response to teachers' pleas for materials, led to the production of a significant bank of task-based primary and secondary CLIL units for three L2s (English, French and German) distributed to all bilingual section teachers in Southern Spain and freely available online (see http://www.juntadeandalucia.es/educacion/webportal/web/aicle/contenidos/). These units, covering natural and social science; mathematics; music; technology and physical education, were designed by expert bilingual content teachers in tandem with researchers providing pedagogical and linguistic support. Reflecting upon the process of their production provides insights into the difficulties content teachers can have in integrating language into their subject teaching and reviewing these materials results in a taxonomy of activity types suitable for each stage of a CLIL task.