Okay, kiddo, so imagine you have a bunch of balls of different sizes and colors, and you want to figure out how they move around each other. That's kind of what scientists do when they make a numerical model of the solar system.
They have a lot of information about the sun (which is a big yellow ball) and all the other planets (which are smaller balls of different colors) and how they move around each other. They put all of that information into a computer program so the computer can "simulate" or "act out" how the planets will move over time.
The program uses a bunch of math to figure out things like gravity (which is what pulls the planets towards the sun), the sizes of the planets, and how fast they're moving. Then, it starts the simulation and shows scientists what the solar system might look like in the future, or how it might have looked in the past.
Scientists use these simulations to make predictions about things like eclipses (when the moon moves in front of the sun) and to learn more about how the solar system works. They can also use them to explore what might happen if something big changed, like if one of the planets suddenly disappeared!
Overall, numerical models of the solar system are a really important tool that scientists use to understand more about space and the things that are happening up there. Do you have any other questions, kiddo?