In this preregistered, longitudinal study of early code-switching, 34 US-born, Spanish-English bilingual children were recorded with a bilingual family member at 2;6 and 3;6, in Spanish-designated and English-designated interactions. Children's Spanish and English expressive vocabulary and their exposure to code-switching were measured through…

This is the first collection of research studies to explore the potential for mixed methods to shed light on foreign or second language learning by young learners in instructed contexts. It brings together recent studies undertaken in Cameroon, China, Croatia, Ethiopia, France, Germany, Italy, Kenya, Mexico, Slovenia, Spain, Sweden, Tanzania and…

The large and rapidly expanding body of literature on bilingual acquisition is mostly comprised of either single-case or cross-sectional studies. While these studies have made major contributions to our understanding of bilingual children's language development, they do not allow researchers to compare and contrast results with regard to…