Chapter 7 is a new chapter that focuses on immersive, exploratory environments. Microworlds enable learners to speculate about phenomena in a simplified representation of the real world, and tobtest hypotheses. This chapter also briefly introduces virtual realities, which are only beginning to find their way into educational venues. Virtual reality environments hold great promise as the most engaging, authentic, and interactive environments yet. The technology is not yet available to make these environments widely available; that will change soon.