I use a standards based grading system so the standards on the assessment are listed at the top. This writing assignment uses the Claim, Evidence, Reasoning format and asks students to analyze the data and give an evidence-based explanation for what they have determined to be the toxin in the city's water supply
The residents of Brockton, MA have experienced trouble after switching their water supply to a new river. This river is located near a chemical treatment plant, and residents fear that their water has become contaminated. After the switch, the water became brown and dirty, and started to taste bad. Many people have become sick from drinking the water, with many side effects reported. The city has hired you, a scientist, to investigate what substance is making the water unsafe. Your assignment is to identify the toxin that is poisoning the water supply.