The class nodded in agreement.
"Then why is it that while I am standing upright in the ordinary position, the blood doesn't run into my feet?" the teacher asked.
A little fellow shouted, "'Cause yer feet ain't empty."
A three-year-old went with his dad to see a litter of kittens. Upon returning home, he breathlessly informed his mother that there were two boy kittens and two girl kittens.
"How did you know?" his mother asked.
"Daddy picked them up and looked underneath," he replied. "I think it's printed on the bottom."