The 17-year-old Irish descendant's essay, titled One Enchanted Evening, was inspired by her love of Irish music and gave an emotional description of a concert filled with folk music and ballads like Danny Boy which she wished would never end.
"When I play Irish music, it brings joy to my heart - it makes me feel happy - and listening to it takes me to another place. It's in the blood."
Competition judge, honorary Consul-general of Ireland Rodney Walshe visited the school to recognise Anna's achievement and said she did not necessarily have the luck of the Irish to have been so successful in the competition.
"She's just got talent - plain and simple. The top three essays in the competition were superb. Anna's ability to describe how she felt when listening to Irish music was moving."
Mr Walshe presented Anna with an Irish Waterford crystal clock to recognise her achievement, but because it contained large amounts of lead, the Irishman had some difficulty getting it through security measures at Auckland Airport.
"It showed up on the airport scanners like a big black box with a large clock face on it."
Anna was delighted with the award.
"When I wrote the essay, it was an expression of my personal feelings. It's nice to know it touched other people as well."
