Reading 3D is an assessment instrument which balances the foundational skills with Text, Reading and Comprehension (TRC) diagnostics, giving a complete picture of a student’s reading development. Teachers administer the TRC to collect a variety of reading and comprehension information. The assessment involves a child reading a passage from a leveled reader to combine quick indications of early skill development with deep observations of students’ interactions with authentic texts. Reading 3D is intended to be used for grades K-5. The assessment can be used for both determining benchmarks and for progress monitoring.