Dirty water can get cleaned up a little bit by small rocks and tree seeds and it can be cleaned a lot by sawdust and paper towel. Nature has all parts in it, in the ground to clean up dirty water. I learned that if you find any metal around the house and connect it to wire and a light bulb it conducts electricity. I learned when the switch isn't touching it, the bulb won't light up because electricity has to go all the way around the circuit without stopping. I learned that lemon juice has a special chemical in it that burns before paper does.
Crystals grow into different shapes.