You can imagine wires being water pipes, voltage is water pressure, current is water flow. It always flows from high pressure to low pressure.
I always used this example when I explained this to friends or youngsters asking this, similar but slightly different example, as at some audiences, like to ask what if the pipe break or burst ? And where the water goes ?

I used wire = blood vein , current = blood "flow" (not the blood it self, but the flow, and the blood must ALWAYS be there in the vein) and voltage = blood pressure, also to spice things up, heart is the battery/power source.
This example, hopefully will suppress the pipe burst question, and my case it worked all the times.

Of course, should they ask about the pipe/vein burst or blood spillage, all I need to answer is .. ITS BAD !
