Why is this the answer?

The answer is pupil because this clever riddle describes the special little window in the center of your eye! The pupil is the small, black circle you see right in the middle of your colored eye part, which is called the iris. It looks dark because it is actually a tiny, round opening that lets light travel into the very back of your eye so you can see all the amazing things around you. The secret to solving this riddle is the clue that says, "Different lights do make me strange, thus into different sizes I will change." Your pupil is a superhero of your eye because it changes its size constantly. This changing size is the "strange" but helpful thing the riddle mentions. It is not changing its shape, but it becomes much larger or much smaller depending on the amount of light around you. Think of your pupil like a smart, automatic curtain. When you step outside on a very sunny day, the world is full of strong, bright light. Your eye needs protection, so your pupil does a quick job by shrinking down and becoming very tiny. This is like pulling the curtain almost all the way closed so only a small, safe amount of light can get in. If your pupil did not do this, the powerful sunshine would be too much and would actually hurt the inside of your eye. Now, imagine you walk into a dark closet or when the sun completely sets at night. It is much harder to see because there is hardly any light! In the darkness, your eye tries its best to gather up every little bit of light it can find. So, your pupil quickly gets wider and much bigger. It pulls the curtain wide open to collect as much of the weak light as possible to help you see shapes and shadows. This incredible, quick change happens automatically, and you do not even have to tell it what to do! That constant movement, from big to small, is why the pupil is the perfect answer to this fun riddle about changing sizes in different lights.