

Sam and Lily were playing with their toy cars on the floor. They liked to make them go fast and make loud noises. Sam had a red car and Lily had a blue car.
"Look, my car is faster than yours!" Sam said, zooming his car past Lily's.
"No, it's not! My car is better than yours!" Lily said, chasing Sam's car with hers.
They raced their cars around the room, bumping into the furniture and the walls. They were having fun, but they did not see that they were making a mess.
"Sam! Lily! What are you doing?" Mom said, coming into the room. She saw the toys and the papers and the books scattered everywhere. She was not happy.
"Sorry, Mom," Sam and Lily said, looking down.
"You need to clean up this mess right now," Mom said. "And be careful with your toys. You don't want to break them or hurt yourselves."
Sam and Lily nodded. They started to pick up their toys and put them back in the box. But Sam saw something shiny on the floor. It was a stamp. A big stamp with a picture of a lion on it.
"Wow, look at this!" Sam said, holding the stamp. "It's so big and pretty!"
"Where did you find it?" Lily asked, coming closer.
"It was under the sofa," Sam said. "Maybe it fell from one of the books."
"Can I see it?" Lily asked, reaching for the stamp.
"No, it's mine!" Sam said, pulling the stamp away. "I found it first!"
They both wanted the stamp. They started to tug and pull on it. They did not hear Mom coming back.
"Stop it, you two!" Mom said, taking the stamp from them. "This is not a toy. This is a special stamp that Dad gave me. It's very old and rare. You could have damaged it or lost it."
"Sorry, Mom," Sam and Lily said, feeling ashamed.
Mom looked at the stamp. She saw that it had a mark on the back. It said "reverse".
"Do you know what this means?" Mom asked, showing them the mark.
Sam and Lily shook their heads.
"It means that this stamp is even more special. It was printed the wrong way. The lion is facing the opposite direction. That makes it very valuable and unique. Dad was very lucky to find it."
"Wow," Sam and Lily said, looking at the stamp with wonder.
Mom smiled. She decided to let them keep the stamp, but only if they promised to be careful with it and share it.
"Thank you, Mom," Sam and Lily said, hugging her.
They put the stamp in a safe place. They decided to play with their cars again, but this time they were more gentle and tidy. They also learned a new word: reverse.
