Okay, so imagine your body is like a big house with different rooms. Each room has its own job to do, like the kitchen is where you cook and the bedroom is where you sleep.
Inside your body, there are tiny things called cells that do different jobs too. They help your body grow and do things like fight off germs when you get sick.
Some scientists found that special cells called stem cells can do lots of different jobs, like they can turn into any other type of cell in your body. So, scientists are really interested in studying stem cells to see if they can help people who are sick or hurt.
Because stem cells are special, there are rules about how they can be used. These are called stem cell laws. The laws say that scientists have to be careful with stem cells and follow certain rules to make sure they are safe to use and don't hurt anyone.
Stem cell laws also make sure that people are treated fairly when it comes to using stem cells. This means that everyone has the same chance to use stem cells if they need them, no matter who they are or where they live.
So, like how you have rules at school to keep everyone safe and fair, there are rules about stem cells to keep everyone safe and fair too.