This paper presents how virtual containers enhance the implementation of STEAM (science, technology, engineering, arts, and math) subjects as Open Educational Resources (OER). The publication initially summarizes the limitations of delivering open rich learning contents and corresponding assignments to students in college level STEAM areas. The role that virtual containers can play in current distant education is then discussed, starting by reviewing related teaching efforts around the use of legacy virtual machines. We then focus on the superseding container technology and how it can bridge the gap between online students, humble computing resources, teachers and IT specificities. As a practical example, we present an experience carried out at the online School of Engineering & Technology at Universidad Internacional de La Rioja (UNIR). Within the context of a subject about Physics for Computing Engineers, we describe the satisfactory evolution from using conventional software distribution methods towards the transition to virtual containers. Thanks to this virtualization approach, the necessary student activities can be implemented, the required software tools can be easily distributed, and the accompanying documentation can be seamlessly presented. The results show how student engagement and satisfaction increased over time, partly because of the easiness introduced by the container technology. Our experience proves that combining containerized educational resources and free and open distribution channels can be one of the cornerstones of a new OER approach in STEAM subjects.