Riddle: What question can someone ask all day long, always get completely different answers, and yet all the answers could be correct?
Answer: "What time is it?"
Riddle: Why weren't the tennis players allowed in the restaurant?
Answer: Because they make too much racquet. 
Why weren't the tennis players allowed in the restaurant? Riddle Meme.
Riddle: What kind of nut has no shell?
Answer: A Doughnut.
Riddle: What has wheels and flies, but it is not an aircraft?
Answer: A garbage truck.
Riddle: What do elves learn in school?
Answer: The elf-abet.
What do elves learn in school? Riddle Meme.
Riddle: I act like a cat, I look like a cat, Yet I am not a cat. What am I?
Answer: Kitten.
Riddle: When John was six years old he hammered a nail into his favorite tree to mark his height. Ten years later at age sixteen, John returned to see how much higher the nail was. If the tree grew by five centimeters each year, how much higher would the nail be?
Answer: The nail would be at the same height since trees grow at their tops.
Riddle: No matter how little or how much you use me, you change me every month. What am I?
Answer: A Calendar.
Riddle: What two things can you never eat for breakfast?
Answer: Lunch and dinner.
Riddle: What can you hold in your right hand, but not in your left?
Answer: Your left hand!