Responsibility
This story teaches children that although they are only young, they still have a certain amount of responsibility. The little boy is told by his mother that she would like him to clean the driveway while she is away, and it is therefore his responsibility to complete the task. The boy is aware of this responsibility and gets stressed when the cat seems to put this at risk.
Reputation
In this story, we see that the cat has gained a bit of a reputation around town, which isn't surprising, given his antics in the original story. Therefore, this shows that people's reputations travel around with them, leading people to make assumptions about a person's personality based on past behavior.
What would you do?
Dr. Seuss' Cat in the Hat series is all about honesty and responsibility. Seuss asks his readers to question what they would do in a similar situation and whether they would tell their own mother about the cat's visit. As such, this tale is a cautionary one about how children should be honest about things that happen to their parents.
Fun
As well as being about a child's responsibility to tell the truth, this book is also about having fun! The silly rhyme schemes combined with the cat's mischievous actions make for a humorous and funny tale about a messy cat who causes destruction wherever he goes.