Why is this the answer?

The answer is reflection because this riddle is a fun and clever puzzle about how light and mirrors work, which is a science topic you might learn about later! A reflection is a picture of yourself that you see in a smooth, shiny surface. Think about looking into a clean mirror or a calm lake. The picture of yourself looking back is your reflection. It looks exactly like you, but it is not the actual you. It is just an image created when light bounces off the shiny surface and into your eyes. The first part of the riddle says, "You saw me where I never was and where I could not be." This is the part that is designed to trick your brain. You see your reflection in the mirror or on the water, but the real you is not standing behind the glass or floating under the surface. The real you is standing outside, looking at the image. The reflection is an image that is "there," but the real person or object being reflected "never was" in that exact spot. The image has no weight, no body, and cannot live outside of its special surface. If you covered the mirror with a sheet, the image would be gone, proving the real you was never trapped inside. Now let us look closely at the next part: "And yet within that very place, my face you often see." This is the important clue that helps you solve the mystery. Even though you are not truly in that place, you definitely see your own face there all the time. This is where the riddle uses the word "me" to mean "my image." You see this image every day when you brush your teeth or get ready for school, or maybe even when you look out a dark window at night. It is an image that is always ready to greet you when the light is just right. So, the riddle is a wonderful way to think about this simple but amazing thing we see all the time. The words describe a picture of you that is seen "within that very place," but it is a picture that has no real body and was "never there" in the first place. This playful trick of words points directly to the answer: a reflection.