When it comes to doing well in the International Baccalaureate Diploma, New Zealand students are doing almost three times better than their overseas counterparts in gaining the top marks.
Of the 430 students who graduated at the end of 2011 with an IB diploma, 13 per cent gained close to top marks - more than 40 out of 45 - compared with the worldwide average of 5 per cent.
Four students, including Carla Boniolo, head girl of Kristin School in Albany, gained perfect scores - something the teenager describes as a "huge surprise".
"I was hoping for a 40 out of 45 - that was my goal going into the exam period," she said. "To get a phone call from my IB co-ordinator at Kristin to say I got 45, it was just one of those surreal moments.
"I was at home with my sister and I quickly phoned my mum and my dad and they thought I was joking. They were very proud."
Carla said it didn't sink in until the results appeared online a couple of days later. The family then went out to celebrate her success.
"I was quite proud of myself because it was two years of quite hard slog and to have the results that I was happy with meant quite a lot; it made those late nights and early mornings worth it."
The perfect scores top an outstanding year for the 18-year-old student, who also co-produced Kristin's charity fashion show, which raised $37,000, and participated in major community events with her prefect team.
She is now preparing to start on Monday at the University of Auckland, where she will study law with scholarships from Russell McVeagh and the university.
Kristin executive principal Peter Clague, who is also chairman of the New Zealand heads of IB, described Carla as an "exceptional young woman".
She was one of many New Zealand students who excelled in the exams, which are sat by nearly one million students around the world.
Mr Clague said the international diploma average sat in the mid to high 20s but New Zealand's was 36 - much to the delight of proud teachers in the 20 schools offering the programme.
Two of the other four top IB scholars, Harim Lee and Elynna Yang, both studied at St Cuthbert's College, which has only recently started the IB diploma. Spokeswoman Kelsey Davis said the school couldn't be happier with the results.
"From our first ever cohort, of 12 girls, 50 per cent received scores over 40. These impressive results are clearly indicative of the talents, motivation and commitment of the students, teaching and learning at the college, but they also demonstrate the growth of the IB Diploma Programme in NZ schools."
TOP EXAM INTERNATIONAL BACCALAUREATE:
*20 schools offer IB or part of the IB programme, which has been in New Zealand since 1986. Eleven schools offered the IB diploma in 2011
*430 students graduated with the diploma, 56 of whom got scores of 40 or more and four who got 45 out of 45.
*The international average score was in the mid to high 20s but NZ stood out with an average rating of 36.
*Carla Boniolo - Kristin School
*Karl Zhu - Auckland International College
*Harim Lee - St Cuthbert's College
*Elynna Yang - St Cuthbert's College.