The team were led well by captain Bridget Johnson but Quirey said Ella-Rose Kini and Jess Pilmer were standouts.
The Girls High team, with players ranging from 14 to 18 years old, placed fourth in the premier women's grade this year - meaning they are used to playing against women with years of experience on them.
Quirey said her team were "very fast, very skill-filled but lack years of experience".
The NZSS competition had the girls playing against others of the same age for a change.
The Marie Fry Trophy win means Girls High will play in the Federation Cup next year - much to their coach's delight.
Quirey said the goal was always to get back into the Federation Cup, meaning a tougher competition next year.
Of the six matches Girls High played, their biggest win was 6-0 against Mt Albert Grammar.
Whangarei Girls High School: Jess Pilmer, Ella Poole-Crowe, MacKenzie Johnson, Katrina Howe, Sara McKean, Michelle Howe, Stephanie Donelley, Anna Miller, Claudia Squire, Ella-Rose Kini, Pialin Sanderson, Ashlee Dobbs, Chloe Neil, Emma Moscrip, Bridget Johnson, Hayley Maunder. Coach: Elma Quirey.