This study explores whether STEM and an engineering design challenge can help English Language Learners acquire academic vocabulary and concepts. The study took place in a kindergarten classroom in a public, suburban school district. Students enrolled in a dual language program comprised of 16 students, nine of which are English Language Learners participated in a unit on weather, in which each lesson allowed students to be involved in a hands-on activity with a final engineering design challenge. This study explored whether students can acquire content related vocabulary and meaning through science and engineering rather than typical ELA practices. This unit consisted of eight lessons that primarily focused on common weather patterns experienced in the Northeastern region of the United States, followed by an engineering design challenge in which students designed a shelter to protect an animal figurine from the rain. Data was collected from pre-and-post-tests where students had to identify 29 key vocabulary words and their matching pictures. The results indicated that STEM and the engineering design challenge indicated significant growth in both vocabulary acquisition and picture identification from the beginning of the unit to the end of the unit. This study suggests that ELLs can acquire academic language through a STEM unit and participating in an engineering design challenge.