Abstract: A system for teaching computer programming includes a computer, a display connected to the computer, software executable by the computer to generate a window on the display, and a user input for transitioning the window between a first configuration and a second configuration. In the first configuration, the window displays an application. In the second configuration, the window displays a programming interface for the application. The system further includes an editor displayed in the programming interface for changing a code listing related to a parameter of a feature displayed in the application. By changing the code listing related to the parameter of the feature and transitioning between the first configuration and the second configuration, a user is able to observe how differences in the code listing affects the parameter of the feature in the application.