The document discusses three main topics related to classroom discourse:
1. It discusses focusing on linguistic practices in school settings, including classroom interaction as a cultural practice, classroom discourse and literacy development, and discourse study of second language development.
2. It discusses classroom discourse as a form of learning, with teachers initiating questions, students responding, and teachers providing optional evaluations.
3. It discusses measuring students' cognition through Vygotsky's zone of proximal development, where guidance from a knowledgeable person allows students to develop skills just beyond their current abilities.