It's perfectly okay if you don't understand every single one of them. For one thing, I make a lot of corny jokes, and you have to be 40 years old to get some of them.
I like all things grammatical, and I had already written several books about parts of speech, and even the alphabet, so everything that makes up a sentence and even a word was covered except for punctuation.
Kids enjoy laughing and are seldom bored when they find something funny. They also ask questions, often to adults, because they understand that the more words they can comprehend about a funny story or a joke, the more they'll enjoy it.
When a kid can understand that a word can mean two things, there's some real thinking going on. They have a vested interest in finding out what a word means, because it's the punch line to a joke.
You want a story? Read 'Gone With the Wind'. These aren't stories. They're joke books. The whole thing of a beginning, a middle and an end has been done to death.
If I have a talent for making some fourth-grader who hates school and reading to hate it a little less, then I have to do the most with what I've been issued.