Phillip Simelane has been formally charged with the murder of 16-year-old Christina Edkins, who was stabbed on a bus in Birmingham last week.
Simelane, 22, from Walsall, was charged with the murder of the schoolgirl after he was brought into police custody from a mental secure unit.
Police confirmed that the authority to charge Simelane was granted by the Crown Prosecution Service following an assessment. He is due to appear at Birmingham Crown Court to face the charges.
Edkins died from a single knife wound to the chest in the morning rush-hour stabbing in Five Ways in the centre of Birmingham on 7 March.
Christina's parents Jason and Kathleen Edkins described her as a "bubbly, beautiful and intelligent" teenager.
They added: "We are heartbroken by the loss of our beautiful princess, Christina, and it's hard to find words to describe the pain we're all feeling.
"Her family and friends will remember her as an amazing individual with her whole life ahead of her. Our lives will never be the same again.
"We've heard talk of protests in Christina's name, clamouring for swift justice. But as a family we'd urge people to remain calm, be patient and let the legal process take its course."