Some researchers are saying that natural language is probably one of the most promising interfaces for use in the long term for simplicity of learning. If this is true, then it follows that speech recognition would be ideal as the interface for computer-based training (CBT). While many speech recognition applications are being used as a means for a computer interface, these are usually confined to controlling the computer or causing the computer to control other devices. The user input or interface has been the recipient of a strong effort to improve the quality of the communication between man and machine and is proposed to be a dominant factor in determining user productivity, performance, and satisfaction. However, other researchers note that full natural interfaces with computers are still a long way from being the state-of-the art with technology. The focus of this study was to determine if the technology of speech recognition is an effective interface for an academic lesson presented via CBT. How does one determine if learning has been affected and how is this measured? Previous research has attempted quantify a learning effect when using a variety of interfaces. This dissertation summarizes previous studies using other interfaces and those …