First, we have just released this fun video about the psychology of yawning. Hope you enjoy it.
So, to the puzzle. Please do NOT post your answer, but do say if you think you have solved the puzzle and how long it took. Solution on Monday.
A boy and a girl are chatting.
“I am a boy”, said the child with black hair.
“I am a girl”, said the child with white hair.
At least one of them lied. What colour hair does the boy have?
I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UK here and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.