1. Identify the city and state: Knowing the location of the school is crucial.
2. Use a watershed map: Once you have the location, search online for a watershed map of that area. Many government environmental agencies (like the EPA or state-level environmental protection agencies) provide these maps. You can then locate the school on the map to determine which watershed it's in.
For example, you could search "watershed map [city, state]" to find a relevant map.