Read the meter and write down the reading. When you return home, take another reading. If the number has increased, you may have discovered a leak. Tell an adult in your house about it. Check your toilet.
Toilets often leak without anyone noticing it.
Ask an adult to take the top off the tank of your toilet. Put about 12 drops of red or blue food coloring in the tank, until the water is brightly colored. Now look at the toilet bowl. If colored water shows up, you have found a leak. Your toilet is wasting energy and should be repaired.