Simplify the following text for a Grade 7 native English-speaking person.
Original: Joanna NoÃ `` lle Blagden Levesque ( born December 20 , 1990 ) , professionally known as JoJo , is an American recording artist and actress .
Simplified: Joanna NoÃ `` lle Levesque ( born December 20 , 1990 ) , known by her stage name JoJo , is an American singer .