Measuring electricity is like measuring the flow of water pushing a paddlewheel. Water passes through the paddlewheel as it performs its work.
Now if you could dam the river that drives the paddle wheel, you could turn the current on and off. This is much like the way electrical appliances work. Switch them on and you are opening the way for the current of power to flow. Switch them off and you are stopping the current of power.
As electrical devices are turned on in your home, an electrical current passes through them. A meter measures all the electrical power that comes into your house. This power is measured in kilowatt hours.

A watt is one unit of power. A kilowatt is 1,000 watts.
A kilowatt hour is the amount of force (1,000 watts) passing through your electric meter over a one hour period.
Ex. A 100 watt lightbulb turned on for 10 hours uses one kilowatt hour of electricity. Or, a 10 watt nightlight kept on for 100 hours uses one kilowatt hour of electricity.
To learn to conserve energy, you must learn different ways to reduce the number of kilowatt hours of energy you use in your home and at school.