In this activity NGSS (Next Generation Science Standards) aligned activity, students (Part 1:) design and carry out a study to calculate how much water will be saved if they turn the water off while brushing their teeth, and (Part 2:) design and carry out a loner-term study at home to calculate how much water can be conserved. The lesson proceeds as follows: 1. First, students watch a short video on water conservation, and the growing water shortage crisis worldwide. They answer a few questio