This Environment: Water & Air lesson plan also includes:
The introduction to the lesson mentions a sailor's limited capacity to store drinking water on his ship. Pupils then set up an overnight experiment to remove freshwater from salt water by distillation. There is a math and map activity to follow. Finally, learners develop a survey for collecting information from their families about water use. The math and map activity seems only weakly related to the topic of freshwater, but the activity would be a strong addition to your water curriculum.