Time
5 min introduction to water quality 20-25 min conduct water quality tests 20-30 min discussion of class results
Grouping
2-3 students
Materials
For whole class to share:
- 1 package removable dot labels or rolls of masking tape
- pH test strips
- dissolved oxygen test kit - Kits cost between $10-60 depending on the type of test. Usually, each kit can perform 50-100 tests. They are widely available at pet stores (for testing fish tanks) and at science supply stores. See the Sources section for a selection of distributors.
- 4 pool or aquarium thermometers
- a stack of disposable paper cups (the 5 ox Dixie cups available for $3 at supermarkets and pharmacies work well)
- various water sources to compare against room temperature tap water
- for the temperature test try water in the sun, ice water, water on black asphalt, water in the shade, etc.
- for the pH test try rainwater, vinegar, muddy water, stream water, bottled water, soda, diluted detergent, fertilizer, fish tank water, salt water, etc.
- for the dissolved oxygen test try water left in the refrigerator overnight, boiled water, water bubbled with an aquarium pump, fish tank water, etc.
Setting
Classroom, although some tests such as water left out on black asphalt might require access to the outdoors.
