The material presented here is based on the experience of CNR ISMAR researchers in their dissemination activities and serves as educational material for students and teachers on the subject of aquatic vegetation in the Venice Lagoon. It is divided into two main parts: a general introduction to marine vegetation; and educational fact sheets on the main lagoon species. The fact sheets are divided into three macro-themes: microalgae, macroalgae, and marine phanerogams. They are a selection designed to give an overview of the richness and variety of the Venice Lagoon. The text is intended as a tool for the reader, stimulating curiosity to study the complex network of relationships between organisms: each fact sheet opens small windows onto important ecological themes that can be explored independently. In addition to text, each section uses drawings to describe biodiversity, as the early naturalists did, but with a different purpose than accurate description. The drawings simplify concepts and emphasize certain details, but at the same time they invite readers to observe biodiversity in real life, on different scales, and perhaps redraw it in their own way and with their own means.