Electrical systems require an energy source (input), a load (output), and a complete loop of conducting material. (refer to energy systems)
When any part of this loop of conducting material is disconnected, the current will stop flowing. A switch is a device that connects and disconnects the circuit. A sensor does the same thing by responding to conditions around it. For instance, an electric heater could be operated by a manual switch, or it could be controlled by a temperature-sensitive switch that turned on and off automatically. A “smart” appliance might have multiple ways to turn it on, or multiple conditions that must be met before it will turn on.
The circuit boxes you have been given have multiple switches, connected in a variety of ways, and two electrical contacts for you to connect your output (probably a light/battery combination).
Once your output has been connected to the circuit box, try all the switches and see if you can find any patterns for how they control the flow of electricity.