This paper describes "Active Essays" and their implementation with Internet technology. An Active Essay combines a written essay, program fragments, and the resulting live simulations into a single cohesive narrative [11]. We believe the integration of programming and natural language makes a superior teaching medium for expressing mathematical, scientific, and even literary ideas. It is especially effective when it can be read, run, and authored in a web browser. We review our previous implementations of Active Essays on the Web. Chalkboard [25] is our latest Active Essay framework. We discuss Chalkboard's features, examples, design decisions, and unresolved issues.