This study analyzes the core vocabulary used by typically developing school-aged English-speaking children in the United States while participating in a variety of school activities. The language of typically developing children, some of whom spoke English as a second language was recorded, transcribed and analyzed to identify the most frequently used words across samples. An inventory of oral core vocabulary of typically developing school-aged children resulted from this analysis. This inventory can be used as a source list for vocabulary selection for school-aged children with AAC needs. Implications for vocabulary selection are discussed.