I can't explain it like you're five, because you're not five and you have been indoctrinated into the classical world. But this video is pretty good.
"Quantum Entanglement & Spooky Action at a Distance "
If you haven't grasped the quantum way of thinking, this next one is a great video. It doesn't get all technical and assumes some basic information, but the pictures should start you in the quantum direction.
"Delayed Choice Quantum Eraser Experiment Explained"
I have what appears to be an apple, and you have what appears to be an identical apple. When I slice mine in half, half of my apple disappears, and half of your apple disappears. But not just any half - the way I cut my apple determines which half you get. If there is a bruise, it will be either on my half or on your half. Putting the halves together gives us exactly the apple that we appeared to have before it was sliced.
In quantum terms, it is much as the video above describes the double slit experiment - the photon or electron goes through both slits, so it is in 2 places at once. That is how we both appear to have the same apple in the beginning. Slice the apple, same as measuring the photon, and it collapses into the two halves.
We can create photons that are not entangled, and they do not behave the same way. What happens at detector 0 in the second video is inexplicable, currently, but that's entanglement.