Anthropic's Prompt Engineering Interactive Tutorial is an official, comprehensive learning resource for mastering prompt engineering with Claude models. The tutorial provides hands-on, interactive exercises that teach users how to craft effective prompts from basic structures to advanced techniques. The curriculum is structured progressively, starting with Basic Prompt Structure fundamentals and advancing through Being Clear and Direct, Assigning Roles, Using XML Tags, Formatting Output, Thinking Step by Step (Chain of Thought), Using Examples (Few-Shot), Avoiding Hallucinations, and culminating in Building Complex Prompts from Scratch. The primary format uses Google Sheets with Claude for Sheets extension for an accessible, interactive experience, though Jupyter Notebook versions are also available for developers who prefer a code-based approach. The tutorial supports multiple Claude models including Claude 3 Haiku for fast and cost-effective learning, Claude 3 Sonnet for balanced performance, and Claude 3 Opus for maximum intelligence. Integration with Amazon Bedrock is provided for enterprise users. Each lesson includes practical exercises where learners write prompts and receive immediate feedback, allowing iterative improvement of prompt engineering skills. The repository has attracted over 31,000 stars on GitHub, making it one of the most popular prompt engineering resources available. An API key is required for interactive exercises, but static answer keys are provided for those who prefer to review without hands-on interaction. The project is maintained directly by Anthropic and represents the official best practices for Claude prompt engineering.