Bullfrog Films - A source of ecology- and environment-related videos and films for all grade levels. Ecosystems Teaching Package - An ecological teaching package for school science classes - may be viewed online or downloaded free. Activities illustrate how different living things (including humans) depend on each other and their environment.. Green issues; helping the ecosystem. (Ages:7-14). Virtual Quarry Interactive - Examines the ecological impact of quarrying, and how quarries can be made sustainable by returning the depleted quarry to a natural habitat Fundamentals of Ecology - Online course which breaks the subject down into sections on populations, community and ecosystems. Microdocs: Short Attention Span Science Videos on Ecological Sustainability - Offers 2-4 minute "micro-documentaries". The first series reveals threats facing coral reefs and showcases people working to preserve this diverse ecosystem. Natural Resources, the Environment and Ecosystems - Activities for teachers to help students become more aware of how plants, animals and humans interact with ecosystems.