For scientific educational purposes, many types of chemical experiments are conducted in academic institutions. However, these experiments in real classroom environments can be quite dangerous and can potentially harm students. To instruct students in conducting experiments safely, virtual chemical experiment applications were developed. However, existing virtual science experiment applications are mostly limited to having only one participant. To solve this limit, this paper describes the design of an interaction engine, enabling interaction among multiple users and implements the virtual science experiment application based on that interaction engine.