🌊 Chicago Runoff Launch

Students examine a short local scenario, images, and a teacher-led runoff tray demonstration showing oil sheen, floating trash, and dissolved colored substances moving across a model Chicago streetscape into the river. As a class, they capture notices and wonders on chart paper and sort them into pollution sources, affected people, and unanswered questions. This launch introduces the challenge and gives students concrete evidence they will use in later writing.