ELI5: when electricity moves, it creates an area around it that pushes on things nearby, and that makes those things move. Some things are more sensitive to that electric force than others, which is called magnetism. It's an invisible force though, just like how you can't see gravity. When something that is magnetic is near electricity, they react to each other and that causes things to move, or glow, or heat up, and other stuff.
Beyond 5:
Most people have electricity explained using the water analogy. That is that electrons flowing through a wire are analogous to water flowing through a pipe. More conductive or larger wires are like having a bigger pipe. More flow equals more electricity, which equals more power.
This isn't quite right. The flow of electrons doesn't create any power. The flow of charged particles creates electromagnetic fields. These fields result in a physical force on objects that are responsive to those fields. Think of it like gravity. Gravitational fields affect matter with mass, and electromagnetic fields affect matter through an inherent magnetic quality. So, the electrons don't actually push on anything, they create an electromagnetic field, and that creates a physical force.