E-learning is playing a significant and increasing role in elementary science education. The purpose of this study was to explore how primary Grade 3 students constructed an understanding of seasons through a series of interactive e-learning activities. One class of Grade 3 students from one local primary school was invited to participate in this study. Methods for data collection included lesson observation and cognitive walkthroughs. Results indicated that the students came to school with alternative conceptions of the seasons, such as the seasons are distributed unevenly or that summer is the longest and includes the months from June to September. Results also indicated that the process of discussing prior knowledge of the seasons through online forums as well as analyzing the weather data of temperature, humidity, and rainfall as evidence to explain seasons helped to facilitate the students' conceptual changes and construction, as well as their awareness and skills of evidence use in scientific explanations. This study has implications for the implementation of e-learning for developing students' science concepts and abilities of evidence use in early elementary education.