This unit provides third graders with a systematic overview of computing hardware and software, computing systems, computer networks, and the internet. After lessons on internet safety, students begin to confront how data is translated into 1s and 0s, and how this the language computers use for all their tasks. The third-grade student then identifies real-work algorithms, and the class begins to create programs using a sequence of commands, sequences, and loops.

The Codes and Computers Student Reader includes nine chapters and a student Glossary providing definitions of Core Vocabulary words. The Student Readers include a feature called Word to Know, which provides background information to help students understand key terms, and may sometimes include additional informational boxes, such as Think About.