Taken verbatim from lifeisajoke.com.
I'M TOO SMART
A first grade teacher was having trouble with one of her students. The teacher asked, "Johnny what is your problem?"
Johnny answered, "I'm too smart for the first grade. My sister is in the third grade and I'm smarter than she is! I think I should be in the third grade too!"
The teacher had had enough. She took Johnny to the principal's office.
While Johnny waited in the outer office, the teacher explained to the principal what the situation was.
The principal told the teacher he would give the boy a test and if he failed to answer any of his questions he was to go back to the first grade and behave. The teacher agreed.
Johnny was brought in and the conditions are explained to him and he agrees to take the test. Principal: "What is 3 x 3?" Johnny: "9".
Principal: "What is 6 x 6?" Johnny: "36". And so it went with every question the principal thought a third grader should know.
The principal looks at the teacher and tells her, "I think Johnny can go to the third grade."
The teacher says to the principal, "Let me ask him some questions" The principal and Johnny both agree.
The teacher asks, "What does a cow have four of that I have only two of?" Johnny, after a moment, "Legs."
Teacher: "What is in your pants that you have but I do not have?" The principal's eyes open really wide and before he could stop the answer, Johnny replied, "Pockets."
Teacher: "What does a dog do that a man steps into?" Johnny: "Pants"
Teacher: "What word starts with an 'F' and ends in 'K' that means a lot of excitement?" Johnny: "Firetruck"
The principal breathed a sigh of relief and told the teacher, "Put Johnny in the fifth grade, I missed the last four questions myself."