The four year old is standing up in my way asking me to carry him to the bathroom to brush his teeth.  I tell him 
"You are too big for me to be carrying you". 
So he squats down and does a duck walk and says "now I'm smaller mom" (with a sly grin on his face) 
Technically, he is correct.  I love this kid, fills my days with laughter.  I will have to explain that modifying his dimensions into a ball does not change his mass.

Me: 'What did you learn in school?'
6 Year Old: 'We are learning about transportation.  Last week was transportation from the past, this week is transportation today, and next week is transportation in the future'
Me: 'Cool, what kind of transportation was there in the past?'
Him: 'The Conestoga Wagon!'
Me: 'What was the Conestoga Wagon?'
Him: 'It was a wagon, pulled by a horse, that only sat two people up front, and it used cloth stretched out over a big bent frame in the back to cover stuff.'
Me: 'Awesome!'

Next Disney educational film, 'Man and the Moon', 1955.  6 year old is watching it and is so excited for me to
watch one part, "Mommy, look these are the rockets of the future, isn't that cool the future!".  He was so excited about them being the 'future' I didn't have the heart to tell him the movie was made in 1955 and we are well into the future from where it was then, and some of them already exist.

Went to check on the four year old at 9:30pm, he was still awake, and he approached stalling bedtime with,
"Mommy, I want to tell you a bedtime story". 
Me: 'Ok, Michael, tell me a quick bedtime story'
Him: "Once upon a time, there was a grown up named
Mommy, and she loved to go on adventures.  In this adventure she is going under the sea.  She drove her car to the beach, and swam out into the water.  But then
she went down a water fall and went 'wheeeee' until she landed back home, The End"
I love this little man, he is so full of adventure, I even get to go on them in his created bedtime stories.  Great end to my night.  They tell me bedtime stories, for building their creative writing and communication skills, and I learn all about new ninja skills I never knew I had.

The 4 year old turned on the Mac to play PBS kids.  I told him the volume was too loud, and went over to adjust it.  He gives me the, 'oh ok mommy, I got it' and hits the right key to turn the volume down himself and continues in his clicking to open the curious George
game without looking away.  I am both proud and a bit worried he might know the password to the adult computer at this point.

Watched 'Our Friend the Atom' (Disney, 1957) with the boys.  The 6 year old loved how they described an atom like a little solar system, where the nucleus is the sun and the electrons are the planets.  He told his little brother he is made out of millions of tiny solar systems, the 4 year old said 'cool'.  They also showed an example of how nuclear energy works with a room full of mouse traps each with 2 ping pong balls on them, and how the chain reaction starts.  I wish Disney still made these type of educational cartoons, they explain concepts so well.