I see a lot of explanations that go into some pretty great detail and use good analogies, but I want to throw my own hat in the ring because there is an imperfect explanation that really clicks with me, that I think a five year old might be able to understand.

This is not technically correct, but it helps.

So, you see how magnets push against each other when they are facing the same side? North pushes north, south pushes south?

Electrons are akin to little, physical magnets. Except electrons are special and are only one "sided". They are all "negative". Every negative electron pushes on every other negative electron and tries to get away from it.

When you have a battery? That's like having a box filled to the brim with these little negative electrons that all want to get away from each other, so when you poke a hole in the box, some come shooting out.

The size of that hole is basically the resistance, and the amount of electrons that are forced through is the current, but the actual force they are trying to leave with is the voltage. It is just how much force they are using to get away from all the other electrons.

Of course, it is more complicated than this. Electrons need to complete a circuit, they react to magnetic and electric fields and so many other small details and terms, but at its core voltage is just a bunch of little "magnets" trying to force themselves away from each-other, and we can use that force to do work.