Electric Circuits
Electric Circuits is the path that lets power flow from a source through wires to run things.
Think of it this way
A water pipe runs from a tank through a hose to a faucet and back. When the path is open, water flows the whole loop without stopping. A closed valve breaks the loop, and water stops moving. Electric circuits work the same way — power flows in a full loop from source to device and back.
Explaining electric circuits by grade level
A circuit is a loop of wire. Power flows in the loop. If the loop breaks, power stops. A sensor on a belt uses a circuit to count boxes.