This is a multimedia course for learners interested in studying environmental science. The Web site provides access to course content and activities developed by leading scientists and researchers in the field. It includes many areas of study using different types of learning materials. The learning materials are augmented with videos and some with simulations such as the food chain. I found the videos informative and the simulations fairly easy to manipulate. I would use the food chain simulation with my own class in our ecosystems
https://www.learner.org/courses/envsci/index.html