The interactive workshops conducted by the students of De Sanctis Deledda coordinated by the teachers illustrate the interactions existing in the microbial communities of different habitats. In particular, samples from salt ponds, well water and the microbiota of insects capable of using “unusual” materials such as polystyrene in their diet will be examined. In addition to representing scientific curiosities, these interactions allow us to understand the existing relationships between the species that make up the microecosystems examined, relationships that nevertheless represent excellent study models for understanding the ecological dynamics that characterize macroscopic ecosystems.