As increasing numbers of culturally and linguistically diverse young children enter preschool through second grade classrooms, teachers are faced with complex challenges as they struggle to meet children's needs. This document is the third of a three-part videotape training series designed for preservice teachers, child care providers, and teaching staff in preschool through second grade classrooms. This third part of the series focuses on core elements of first and second language acquisition. Segment 1 of the video covers language acquisition, reviewing the critical role adults play and demonstrating how second-language learning is built on the base of the child's first language. Segment 2 covers comprehensible input, and show how to assist children in connecting words with meaning, offers a strategy for providing rich language input, and demonstrates how multi-sensory learning activities help children make sense of language. Segment 3 addresses the silent stage that children acquiring a second language go through, and emphasizes that this is actually a period of intense language processing and demonstrates how children who are not yet speaking are still communicating. The final segment shows how being singled out or embarrassed closes a child's affective filter, reducing a child's ability to learn; this segment also demonstrates how to foster English language learners' participation, and how peer support can contribute to children's success. The accompanying trainer's guide includes discussion starters and interactive exercises. (HTH)