This activity will show kids how light reflects and bends as it comes in contract with water.
Rather than shining straight through the water bottle, you should have noticed the flashlight’s light following the path of the streaming water. This is because water is actually a really reflective substance. So much so, that it reflects off of itself. The light initially travels straight through the water, but once it hits the edge, it reflects in the opposite direction. It keeps reflecting off of the water until the light exits onto your hand.