This study explored how one eighth grade girl learned about the structure of recursive programs in BOXER programing language. The method of impasse resolution was presented in detail and used both to understand how she constructed her understanding and as an empirical method to analyze her learning. (MDH)

This study examined the representations that a 16-year-old student made using the flexible computer system, "Boxer," in learning the genetic code. Results indicated that programing made it easier to build and explore flexible and useful representations and encouraged interdisciplinary collaboration between mathematics and biology…