Association for Public Policy Analysis & Management

With an increase in immigrant and refugee families in many countries around the world, the question of how best to prepare the children of these families for schooling and further education becomes salient. One dominant theory suggests that by teaching immigrant children their mother tongue – i.e. the language spoken at home by their parents – their proficiency in the language of the receiving country will improve. This may happen because stronger skills in their mother tongue may give them a better foundation for learning an additional language (Goldenberg, 2011). Systematic literature reviews have found positive effects of mother-tongue teaching (Cheung & Slavin, 2012; Slavin & Cheung, 2005). However, most of the existing studies are based on observational studies, and the few randomized controlled trials are low powered (Taylor & Fintel, 2016). To improve evidence for policy-making the Ministry of Education in Denmark initiated a randomized controlled trial of mother-tongue teaching. 34 schools participated in the first year and 36 schools in the second year of the study using cross-over randomization. In total 451 students participated. In the paper we present the results of the trial, both the short-term outcomes on mother tongue proficiency and student well-being and the medium-term outcomes on the Danish language skills. Besides presenting strong evidence on the effect of an important policy for educating immigrants, the project also speaks to the 2018 APPAM conference theme by demonstrating the benefits and challenges when national and local governments work together to improve policy evidence.