The Convention on the Rights of the Child states that children from minority groups have the right to learn, use and develop their indigenous/minority languages, and a primary goal for the Sami school in Sweden is to support each child’s functional Sami-Swedish bilingualism. However, Sweden continues to receive criticism from the Committee of Ministers of the Council of Europe for the lack of a comprehensive and structured approach towards minority language education, resources, materials, and teacher training. Oral language development is central to a child ́s ability to access the curriculum and develop literacy skills. All children need an environment supportive of oral language development, and opportunities and interactions with more knowledgeable conversational partners to practice and develop oral language skills. Little is known about how bilingual children’s oral language development in Sami and Swedish is supported. Teachers can be supported by tools that they can use to describe the language learning environments, opportunities and interactions, and to develop their professional practice in the area of effectively supporting young bilingual children ́s oral language development. We report on a pilot study that has adapted the Communication Supporting Classrooms Observation Tool to the Swedish school context. This adaption is a first step towards adapting and using this tool in bilingual North and South Sami (pre)schools. The results of the pilot study are discussed in relation to the challenges of setting up a research project examining the support of oral language development in both the indigenous Sami languages and the national language Swedish.