Development of German reading comprehension in two-way immersive primary schools

Two-way immersion (TWI) is a variant of the increasingly popular bilingual instruction. Most TWI research lacks longitudinal data or the consideration of background variables to control for possible selection effects. This article examines the development of German reading comprehension of TWI students (N = 984) from fourth to sixth grade compared to conventionally taught students (N = 992). The latent growth curve models showed that immersion students reached the same level of German reading comprehension over the three measurement points, even if background variables like first language, socioeconomic background, and cognitive ability were included. Despite reduced instruction in German, TWI students showed the same reading comprehension level as students in regular instruction while having the advantage of learning an additional language. Although the level of reading comprehension differed between language groups (L1 German speakers, L1 partner language speakers, simultaneous bilinguals), the learning trajectories of reading comprehension were similar.