The teacher announces that she is going to hold something behind her back, and the students have to tell her what she has behind her back.
First she holds a ruler and says, "It’s long, hard and you can measure with it."
A little girl stands up and says, "It’s a ruler."
The teacher replies, "Very good, I like the way you think."
Then she holds a apple behind her and says, "It’s red, round and you can eat it."
A little boy stands up and says, "It’s an apple."
The teacher replies, "Very good, I like the way you think."
Now little Johnny stands up and says, "Teacher I have one for you."
Little Johnny sticks his hand in his pocket and says, "It’s round, hard and has a head on it".
The teacher screams, "Get to the office!"
Little Johnny smiles and says, "It’s a quarter