When asked what water pollution is, most students can readily explain pollution as trash thrown away by humans that enters our water. Students can readily identify items visible to the naked eye, such as cigarette butts, plastic bottles, and bags. This type of debris is certainly a water-pollution problem. However, when students are asked about other sources of water pollution, they may be lost or not able to identify invisible pollutants. Chemical released by manufacturing, cars, and lawns and farms are large contributors to water pollution but can be hard for students to identify because they may not be visible, or the source of the pollution is not easily connected to the area that is impacted. For example, yard fertilizers and pesticides run into storm drains and simply "disappear" from students' world. Likewise, if students are asked how pollution gets into water, they may point to littering but not identify different types of runoff. It is important that students understand that there are many pollutants that get into the water—in different ways—so they can better understand how to prevent pollution from entering the water systems in the first place.

Watch this video of 6th grade students in San Diego, California—a coastal community. The purpose of this classroom video is to see students share their ideas about water pollution.

For additional classroom context, video analysis, and reflection opportunities, read the Picture of Practice page for "What Is Water Pollution?" in the Earth's Freshwater Educator Guide, page 80.