Damn…I’d seriously consider jumping off the plane. Talk about your captive audiences… 
When I was a miniature, my Joke, told to everybody that mistakenly got in my line of sight, was:
Why did the chicken cross the road? To get to his girlfriend!
Paroxysms of laughter ensued. By me only, of course. Often I wouldn’t even get to the punchline. Just fall over laughing, lucky for those in hearing range. I distinctly remember telling it to many grocery store or Wal-Mart cashiers and baggers. I feel so sorry for them. I am fairly sure that was the only deliberate joke I ever made up. I got lots of joke books as gifts for several years after that.
Oh, you just haven’t lived until you’ve heard one of Cranky Jr’s jokes. Zappo came up with the term “Doppler jokes” to describe them, too, because he tells them while running from room to room. They’re great. 
I have a four year old and a six year old. My six year old has finally started to understand the importance of a real punchline, and told me a pretty good one the other day.
Her: Hey mom, why did the peanut cross the road?
Me: I don’t know, why?
Her: Because it was stapled to the chicken!
I liked that one.
I heard a reasonably good joke tonight.
What’s invisible and smells like carrots?
Bunny Farts.
Just never ever ever buy a book called "1000 stupid jokes’, because they are all just as the title tells. My eleven year old loves to announce that he is off to take a dump. He then leaves the door open and proceeds to tell at least 20 “stupid jokes” per dump.
I shouldn’t laugh because it only encourages him, but there is something funny about hearing…
"Why aren’t you married?’
“I was born that way”
…bellowed from the loo. Of course it’s not the joke that’s funny more the fact that just down the hall, there is a child sat with boxers round his ankles, who feels it is just the right time to have a giggle-fest.
AAARRRGGHHH!!
Must…gouge…out…mind’s eye!!
That’s an image I don’t need bouncing around in my skull.
Here are some words that rhyme with “Corey:” Glory…story…allegory…Montessori…
I really hope this won’t be deleted cos its the funniest thing I’ve ever heard coming from a kid.
Some years ago in UK there was a Sunday morning radio show hosted by a well known comedian. Every week kids would phone in and tell a joke (usually along the lines of “Knock knock”…“Who’s there?”…“Atch”…“Atch who?”…“Bless you”). The host would go along with the joke, even if the punchline was obvious, and roar with laughter when the punchline finally came. The kids would get a prize for being on the show and at the end the comedian would choose his favourite joke of the morning and the kid that told the joke would receive a bigger prize.
Anyway, one Sunday morning a young boy gets on air…
Some general chat with the boy
Comedian- “OK then, whats your joke?”
Boy- “Which vegetable makes your eyes water?”
Comedian- “Eh…an onion?”
Boy-“No, its a turnip”
Comedian-“How does a turnip make your eyes water?”
Boy-“Have you ever been hit in the b@lls by a turnip?”
Stunned silence!!! No one I’ve spoken to knows how the call ended cos everyone across the country was laughing so much…priceless!!
My 3 year old insisted on checking out a book of knock-knock jokes from the library a few months ago. I knew he wouldn’t understand the wordplay, but something about the cover grabbed him. So for the next week we ended each day with sampler platter of jokes he didn’t get, but over which he was willing to laugh hysterically.
Then came the knock-knock-knock-offs:
knock knock
who’s there?
Althea
Althea who?
Althea later, alligator
became:
knock knock
who’s there?
goodbye!
goodbye who?
alligator says bye bye!
And I’m ashamed to admit it, but I ended up dissecting a joke for him. I explained why the ‘orange you glad I didn’t say banana’ joke was funny, and the lights went on. He still tells it to anyone who’ll take the knock knock bait.
Now, thanks to these guys, most of his jokes end with the line: They threw him out the window!
When my younger brother was about seven, he used to make up incredibly weird greeting cards with our father’s printer and give them out to every family member on their birthday. One that sticks in my mind, and one I have never been able to figure out is this one: A birthday card to our grandmother, which on the front said “To A Wonderful Grandmother”, and inside read, simply “You fill our hearts with joy” and was signed by him. I’m fairly certain he had used a pre-made greeting card setting for that. However, upon turning the card over to read the back, these cryptic words were written:
“Nanny you will always be as pretty as a bald potato. I love you.”
Knock knock
Who’s there
Hair
Hair who?
Hair on your head!
Why did the chicken cross the road?
To get to the gas station!
I think this was a mix of the chicken and the turtle (to get to the Shell station) road-crossing jokes, but it was my son’s favorite when he was about five.
My yougest was fond of the interrupting cow joke and another cow knock-knock that I can’t remember right now, but the biggest laugh she ever got was when she was about two. She had heard the “old lady” knock-knock (I didn’t know you could yodel) somewhere and one night in the car she piped up from her car seat with:
Knock knock
Us:Who’s there?
Her: Old lady
Us: Old lady who?
Her: Grandma Warning!
We laughed so hard! And so did Grandma when I told it to her.
But one of the most fun things was watching that kid learn how jokes really work. She was about five and you could almost see the thought processes. All of a sudden she was seeing the sense of the punchlines and it just made her so happy! “I get it!” she would cry and just grin all over. There’s a song that the Statler Brothers do about remembering old-time things, and it includes the lines:
Knock knock
Who’s there?
Dewey
Dewey who?
Dewey remember, yes we do
And then it goes into the rest of the song.
Well, she’d heard it dozens of times, but one day she looked up with her face all lit up - “Daddy, there’s a joke in that song, and I get it!” In its own way it was as funny as any joke she ever told.
My younger sister invented this one at about the age of three. She thought it was hilarious. I was just the right age to be completely unamused – too old to find it genuinely funny, too young to find it cute.
SIS: What’s the difference between a coconut and a melon?
ME: What?
SIS: A coconut isn’t yellow when you bust it open! Ha ha ha!
I’m old enough now that it makes me giggle a bit. 