The document summarizes the goals and progress of a project to develop Mandarin immersion curriculum with a STEM focus for elementary schools. The project aims to 1) develop interdisciplinary units integrating language, culture and content, 2) provide teacher training, and 3) assess student language proficiency. It discusses lessons learned from adapting an existing STEM unit to the immersion context. Key considerations included strengthening the curriculum team's expertise, rethinking language and literacy expectations, focusing first on content then language objectives, and ensuring lessons support effective immersion instructional strategies.