Korach was a man who was upset with some of the leaders in the community. He thought they were getting too much power and weren't sharing it fairly. He went around and convinced some other people to join him in his rebellion against the leaders.
Moses, the person who led the community, tried to talk to Korach and his followers but they didn't listen. They thought they were right and didn't want to change their minds.
To resolve the problem, Moses proposed a challenge. Each person would bring a special incense offering and laid it before God at the same time. Whichever offering God accepted would show who was right.
When they did the challenge, God accepted Moses' offering and not Korach's. This showed that Moses was right and Korach was wrong.
After this, there was an earthquake and a fire that came from God which swallowed up Korach and his followers. They were punished for not listening and trying to rebel against the community leaders.
The moral of the story is that we should always try to work things out peacefully and listen to our leaders. It's not good to try to cause trouble and go against others without thinking things through first.