Okay, kiddo, you know how sometimes you really like something, like candy or watching TV? Well, imagine there's something that looks like candy, but it's even bigger and sweeter than regular candy. Or imagine there's a TV show that's even more exciting than your favorite show. This is what we call a "supernormal stimulus."
Basically, a supernormal stimulus is something that looks or feels really amazing, even better than the real thing. This can happen with animals, too. For example, there might be a fake bird that's extra colorful or has bigger feathers than a real bird. Another animal might see this fake bird and think it's even more awesome than a real bird!
But here's the tricky part: sometimes, we can get so focused on the supernormal stimulus that we forget about the real thing. We might eat too much of the fake candy and get a tummy ache, or watch too much of the exciting TV show and forget to go outside and play. So it's important to remember that while supernormal stimuli can be really fun, we still need to pay attention to the real world, too.