The Otago Girls High School pupil won a trip to New Caledonia and will also take part in a school exchange trip to France.
Crystal entered the 2008 Alliance Francaise de Dunedin French speech competition in August and was placed first in year 12.
The competition was sponsored by Air Calin, of New Caledonia, along with Alliance Francaise, a worldwide organisation which promotes French language and culture.
Winners in each age group went into a national draw, from which five people were awarded a trip to New Caledonia.
"I think I'm so lucky," she said of her success.
For the competition, she had to participate in an interview in French and was judged on her sentence structure and information she gave.
"I want to thank Miss Kruger because I think she was a really big part in my success in this competition," she said of her school teacher.
She will fly to New Caledonia today where she will spend two weeks living with a family in the town of Poindimie on the east coast.
"I was told to bring my snorkelling mask," she said, as the country is known for its diving.
After hearing of a fellow pupil enjoying the beautiful waters, Crystal was keen to explore them herself.
Poindimie had a population of 4000 and she was looking forward to a "fun adjustment" to life in a small village.
"I've heard it's beautiful."
She did not think she would be participating in many lessons but had her own plans to improve her speaking skills.
"I'm hoping to improve my French, especially fluency and confidence."
After participating in a "crash course" at Balmacewen Intermediate when she was 12, Crystal was hooked on the language.
"I'm really passionate about French," she said, and believed when someone was passionate about a subject, it did not feel like a chore to study it.
She described the language as "romantic sounding" and fun to speak.
"My ultimate goal is to be fluent," she said.
She will leave on her exchange to France the day after she returns from New Caledonia.
She will be staying, again with a family, in Bourges, south of Paris and will then host a French pupil in return next year.
"Doing both [trips] is fantastic. I'm so excited."
