Katu, who set the intermediate discus record in 1993, said if anyone was going to break her record she was glad it was Marina.
"I have been at Girls' High as a teacher for 10 years, and every athletics day I have been really nervous about my record and dreading and hoping that no one would get it.
"But this year I approached Marina and said I think she should go for it and really go hard."
Marina broke the record on her third throw in the discus event.
"I went up to watch the discus and her first two throws were close but her third throw, I knew when she threw it that she had got the record.
"She had tears in her eyes and I was thinking I should be the one crying because it was my record," Katu said with a laugh. "But it was really special being able to record it and be the one to congratulate her."
A softly-spoken Marina said she was rapt to break the school records and said there were no words to describe how she was feeling after the events.
"And that is her, she is so humble," Katu said. "If my record had to fall to someone, it could not have fallen to a more genuine and humble person."
Marina is not only a thrower.
She will tell you her main goal in sports is to be a Silver Fern and she made the Rotorua Girls' High School Senior A team in Year 9.
She also plays basketball, softball, touch, volleyball and dabbles in table tennis and badminton.
"If I don't make it with netball I will go for the Olympics but I am trying for the Silver Ferns."
After injuring her knee last year in netball, she turned her focus from being a sprinter to throwing, which has really paid off this year.
She has qualified for the Mid-Island secondary school athletics next month, which is followed by the Waikato champs then the national champs.
Marina said she had been training hard on her discus and her favourite event javelin this year with her coach and father, Daniel Beazley.
Marina is the youngest of four children and she has three older brothers who she likes to compete against in sport. She thanked her father and mother, Alice Tahana, for their support.
While her records were set in the intermediate grade (under-16) she actually surpassed the senior javelin record at Girls' High as well.. No other student broke a record at Rotorua Girls' High School this week.
- Her record throws (old records in brackets): Shot put 10.45m (10.35m), Discus 29.69m (29.10m), Javelin 32.60m (30m).