ensign siegel

Electricity travels at the speed of light 'along' a wire we are taught. But isn't the electron drift in a wire very slow even when the battery is connected? What is the 'electromagnetic wave' that travels along a wire if it isn't electrons. Or is it electrons? I'm confused. And since I'm a primary school teacher, if I'm confused so are the pupils. Has anyone an explanation I can understand with some basic physics?