Students are to record their answers onto the activity sheet and each student is to plot a graph. Advise students to select points on the graph that they suspect have high or low DO levels. Explanation Students are to make sense of their exploration. They are to find patterns and relationships and answers to questions. Students are urged to explain their findings and to demonstrate their understanding.
Students are to prepare an outline of their findings.
Each group will make a one minute presentation on the possible reasons for high oxygen levels. Elaboration Students are given opportunities to apply the concepts and skills that they have acquired to different situations. Supersaturated oxygen river water may be caused by several reasons. Review several ways in which oxygen enters into water. At this point, the teacher is to introduce the DO kits and provide a brief explanation of how they work and what they measure.