Electric trains have many components that use electricity.
They have an electric horn.
They use an overhead wire and sliding contact to make the circuit.
They have an electric motor that drives the train.
There are coloured signal lights and there are flashing lights at crossings.
Using simple materials such as cells, wires, globes and magnets you can make models of these devices. The following illustrates some possibilities. You could invent others.
The working model below is a buzzer. It works like many electric bells and some horns.
Sliding contact (nerve tester)
The nerve tester sliding contact device is similar to the overhead sliding contact of the train.
However, the nerve tester can be used to test your skill. Can you move the sliding contact from one end of the overhead wire to the other without touching it?
Electric motor 1
To start the motor, you need to flick the coil or twist the ends quickly. You may need to fiddle to get it to work, but when it works, the coil twirls around at a rapid rate.
Electric motor 2
The magnets will have to be supported level with the coil. Up to 30 turns of thin insulated wire is needed for the coil, but it will work with less.
To reduce the effect of the friction of the brushes mount the two pins close to the axle shaft. The cork needs to be well balanced.
Closer to home
You could make a model of your front door so that when you push a button a buzzer or bell rings, or when you open the door the porch light comes on.