The goal of the competition was to write a song for the The Kiwileles, a massed children’s ukulele orchestra.
As well as winning a $300 Rock Shop voucher and an electric ukulele her song will be taught to pupils across the country.
Her song, called My Imagination was about how we should "keep dreaming and keep believing" throughout life.
Anna said Otago Girls’ music teacher Eugene Shields had been "amazing" at helping her discuss different songwriting ideas.
She was also grateful for the mentorship of Dunedin musician Abby Wolfe, who visited the school and gave advice on composing, recording and producing a song.
"It was very helpful because that is how I recorded my demo entry of this song into the competition," Anna said.
It was "really, really awesome" to know children across the country would be learning her song.
"I thought it was a really amazing competition and I want to make sure that everyone out there just continues to dream and believe in themselves because anything is possible. "
She hoped to continue songwriting and performing.
"My biggest dream would be to write songs for very popular artists or to become an artist myself, and just keep playing, I just want to keep playing and playing."
