Web-based homework (WBH) is an increasingly important phenomenon. There is little research about its character, the nature of its impact on student performance, and how that impact evolves over an academic term. The primary research questions addressed in this study are: What relevant factors in a WBH learning environment impact students' performance? And how does the impact of these factors change over the course of an academic term? This paper examines and identifies significant factors in a WBH learning environment and how they impact student performance. We studied over 300 students using WBH extensively for their coursework, throughout a semester in an undergraduate class at a large public university. In this paper, we present factors in the WBH learning environment that were found to have a significant impact on student performance during the course of a semester. In addition to individual and technological factors, this study presents findings that demonstrate that frustration with IT use is a component of the learning environment, and as a construct, has a larger impact than usefulness on student performance at the end of a course. Our results indicate that educators may benefit from training students and engaging them in utility of co-operative learning assignments to mitigate the level of frustration with the software in the WBH learning environment and improve student performance.