Determine Class Water Use Average
Each student in the class should write the "Average Daily Water Use" number that they calculated for their household on the board. Add up all of these numbers and then divide by the number of students in the class to get one average for the entire class. This number represents the average amount of water used by one person in one day. This is the number you will submit to the project database in a later step.

Observations
Think about your results. How does your class average compare to the U.S. national average domestic water use of 80 -100 gallons per person per day (approx. 300 - 375 liters per person per day)? What factors might account for any difference or similarity in the values?  Do the results surprise you?