The Is Our Surface Water in Danger? unit consists of eight sessions divided into three parts. Before beginning the unit, students complete the Pre-Unit Questionnaire. Then, in Sessions 1-4, they use observation to collect qualitative data. They consider water as an important natural resource and discuss ways in which living things use water. Then they visit a local body of surface water and examine it for signs of pollutants. Back in the classroom, they observe the turbidity of the water and screen it for coliforms.

In Session 5-7, students take measurements to collect quantitative data. They measure the amount of oxygen dissolved in their surface water and the pH of the water. These measurements lead students to a deeper understanding of what turbidity and the presence of coliforms imply about the quality of their water. At the end of Session 7, students send their data to the unit database.

In Session 8, students discover what they can learn from display and analysis of the data in the unit database. At the end of the unit, they complete the Post-Unit Questionnaire.