This document discusses various theories of reading instruction. It describes early theories from Thorndike, Gray, and Goodman that viewed reading as a developmental process involving word perception, comprehension, reaction, and synthesis. Later psycholinguistic theories proposed reading involves using graphophonic, syntactic, and semantic cueing systems simultaneously. The interactive and transactional theories of the late 20th century proposed reading as an interactive process where the reader interacts with text and prior knowledge. The document also discusses principles of balanced reading instruction incorporating skills, strategies, literature, and writing.