Work Sample & Commentary: Acid Rain
The task
Students designed and constructed a device to collect and measure rainwater. They recorded rainfall amounts and also tested samples of rain with pH paper over a three-month period, and compared their data with regional data collected by the National Weather Service.

Circumstances of performance
This sample of student work was produced under the following conditions:
alone in a group
in class as homework
with teacher feedback with peer feedback
timed opportunity for revision

This work sample illustrates a standard-setting performance for the following parts of the standards:
c Scientific Thinking: Use evidence from reliable sources.
f Scientific Thinking: Work in teams.
a Scientific Tools and Technologies: Use technology and tools.
d Scientific Tools and Technologies: Acquire information from multiple sources.
a Scientific Communication: Represent data and results in multiple ways.
b Scientific Communication: Argue from evidence.
b Scientific Investigation: A systematic observation, such as a field study.



What the work shows
 c Scientific Thinking: The student uses evidence from reliable sources to develop explanations.
The students gathered data from classmates and web sites on the Internet. They compared their data and the class data to the experts data to verify their conclusions.

f Scientific Thinking: The student works in teams to collect and share information and ideas.
The students produced and compared charts of their own data, the class’s data, and data from the Internet.

a Scientific Tools and Technologies: The student uses technology and tools to observe and measure objects, organisms and phenomena directly, indirectly and remotely.
Students designed a simple device to collect and measure rainfall. They used tools such as a ruler to measure rainfall in inches, and a graduated cylinder to measure sample volume in milliliters.
The students used indicators to test samples of rain. They observed that the pH of the samples caused chemical reactions that produced color changes in pH paper, and they correctly concluded that the rain samples were acidic.

d Scientific Tools and Technologies: The student acquires information from multiple sources such as the Internet and experimentation.
The students utilized the Internet as a data source. In addition, the students utilized the computer for word processing and spreadsheets.

a Scientific Communication: The student represents data and results in multiple ways such as numbers, tables and graphs.
The students organized and presented data in a series of tables and graphs. They attempted to maintain a degree of uniformity in the style of their graphic presentations.

b Scientific Communication: The student argues from evidence; such as data produced through his or her own experimentation by others.
In the first paragraph of the conclusion, students argue for their hypothesis from the evidence of their own and others’ data. They also correctly note the significance of the geographic difference between their own data and the data they accessed on the Internet.

b Scientific Investigation: The student demonstrates scientific competence by completing a controlled experiment, such as a field study.
The students built their collecting apparatus and used it for a period of three months to collect data from natural phenomena that occurred outside the classroom.