This unit was taught at Shasta Elementary over a 4 day course period, in 1 hour and 15-minute lessons. These lessons were taught in two different classes. This is a culminating unit that requires extensive background knowledge. Over the course of several months, students learned about fresh water sources, problems with water, and water conservation represented by inquiry charts and persuasive essays. Students were able to draw from their previous knowledge to explore contaminants, ways to clean water, and the creating of filtration systems. Students acted like scientists and engineers in groups through the exploration of different materials to create a filtration system that would meet criteria with both limitations of constraints. The teacher acted as a facilitator to help guide learning, comparing different solutions before creating one last design as a whole class through comparative research and results.