Abstract
The objective of this study is to develop an adaptive web-based learning system for the scientific concepts of water cycle in primary schools. It is implemented on a SCORM based platform to meet international standards and local necessity. The theory behind its operation is based on constructivism. The system uses diagnostic tools to find out the misconceptions of students by two-tiered test items. Adaptive learning modules were developed by rule-based inference engine to provide remedial instructions for students according to their misconceptions. An experiment was conducted to analyze the learning effects of students and the conceptual changes during their learning processes, and the results can be used to improve the design of system and its learning contents.