The traditional teaching mode of laboratory classes was rigid, with post-graduate tutors giving out lectures before each laboratory session. Students relied heavily on these pre-laboratory lectures to feed them up with the information about the experiments, instead of reading the laboratory manuals themselves. This resulted in spoon-fed teaching and learning pattern. Class time was inefficiently spent as the tutors endeavored to instruct the students stepwise. The students also failed to undergo cognitive learning via achieving the various problem-based tasks in the experiments. To improve the situation, Online Self-learning Systems (OSS), which consist of Echo360 lectures, online demonstration videos and quizzes, were developed to help students build up expectation for the experiments, and hence allowed them to identify any deviations from the expected results for moreadvanced investigations. As a result, students displayed more active participation in the laboratory classes since they were better prepared for the experiments and the class time could be contributed to more in-depth discussion.