Crown attorney Fara Rupert said the teenager's greed drove her to lure other teens into prostitution.
The girl was arrested in June 2012 and pleaded not guilty to 33 charges, including human trafficking and sexual assault.
Rupert said the accused was motivated by "her desire for instant and material gratification."
She said the teen used threats, coercion, violence, alcohol and drugs to lure other teens into having sex for money.
She described the teen as the "boss of an organized crime scheme" that had little regard for the physical and emotional damage she was inflicting.
Two other teen girls who were charged at the same time in connection to the alleged prostitution ring reversed their not guilty pleas late last month.
Closing arguments will continue Tuesday.