Talisha entered the jazz, classical, contemporary and open categories for solo guitar.
However her talent does not end there. She also plays bass guitar, drums and piano.
So does a musical career beckon? Talisha says she is unsure what she would like to do after she finishes school this year but will continue to improve her guitar skills.
Talisha and the rest of the 15-strong New Zealand team also received a gold medal for team spirit and a bronze medal for their group dance. The competition ran from July 11-19.
The judges included some of the most respected entertainment industry experts from Hollywood, Nashville and New York.
In a boot camp before the competition participants got the chance to listen to speakers who had worked with some of Hollywood's biggest stars including Channing Tatum, R. Kelly and Katy Perry.
The New Zealand team also took out a couple of days to visit Disneyland, Hollywood and do some shopping.
Organiser of the New Zealand team, Dina van Rensburg, said she was very proud of Talisha.
"Talisha was amazing.
"She's a quiet girl but she knows what she wants," Ms van Rensburg said. "She's very talented."
Ms van Rensburg, from Accolades International Marketing, had organised the New Zealand WCOPA for eight years now and said this year's team was particularly special.
It was the first year New Zealand won the team spirit award which was quite impressive, she said.
"The fact we are such a small country and such a small team it's such a great achievement," Ms van Rensburg said.
The New Zealand team won many more medals individually, with one person winning 12.
Talisha had to fundraise about $12,000 for the trip but hopes to return to the WCOPA.