Her dream is to follow her heroes, Portia Woodman and Charmaine Smith, and play for the World Cup-winning Black Ferns and she has the 2024 summer Olympics NZ Women's Sevens team in her sights.
But for the next three years, her options are limited to playing sevens, if she can find a team at her new school; and 10s - played virtually nowhere other than New Zealand.
Katrina, who plays openside flanker and right wing, can also join a "composite" team - made up of students from more than one school - but as NZ Rugby rules state these teams are ineligible for tournaments, she wouldn't be able to play any other teams.
Getting facilities in schools isn't a quick fix, says Rugby NZ's head of women's rugby development, Cate Sexton.
"At some point, the decision to divide girls and boys has to be taken. We are guided by World Rugby, so once you hit secondary school, teams and competitions are single sex only.
"Helping players of Katrina's ability is challenging, but ... we've put a lot of time and energy into lifting the profile of the game.
"This year the Black Ferns won the World Cup for the fifth time, and there's been more interest than we've seen before. People are beginning to recognise the players, which we're very proud of. Our next job is to look at supporting secondary schools.
"A lot of girls like Katrina are in limbo, because although it's a growing sport, we don't yet have the infrastructure in place for them to be able to play at most schools. We are working on it, ... but it's important to understand that girls' rugby is a new concept in schools. Changes don't happen overnight."
Katrina's dad, coach and "biggest cheerleader" Andrew Hall will continue to coach the girls' sevens team at her secondary school, Westlake Girls High School, next year, but says there's a long way to go to get her the training she needs to reach her goal.
Katrina is all too aware of the differences between men's and women's rugby.
"The Black Ferns don't get paid, don't get good uniforms and their tournaments aren't organised the same way the men's rugby is - the Black Ferns got just four days to train and rest between the semifinal and the final of the World Cup this year, while the men got two weeks.
"They also flew home in economy - you don't see the All Blacks doing that!"
The Weekend Herald revealed yesterday that negotiations with NZ Rugby to get the Black Ferns a pay rise are set to start, and new Sport Minister Grant Robertson has already called for pay parity with the All Blacks.
Despite the challenges, Katrina is determined to continue playing.
"Sometimes I feel like I'm really fighting to play, but I'll keep working hard to get noticed. I love it too much to give up."
