How much water was used overnight?
Find out where the school water meter is.
Read the meter as school finishes in the evening and Read the meter again as school starts.
Evening reading:
Morning reading:
If there is a large difference there may be a leaking pipe.
Read the meter at the same time each week.
Reading 1:
Reading 2:
(Reading 2 - Reading 1) / 5 = daily water usage