"Having it in the timetable now means there is more revision time in class and more focus compared to in break time. I think that's another factor in the results going up."
Prasad said the Cambridge course offered a wider range of maths than NCEA, and put students in a good position to try for tertiary scholarships in Year 13.
"These students are choosing two lines of maths, because they love it so much.
"They do normal maths with NCEA, and then Cambridge as well.
"By the time they get to that tertiary level they'll be really confident in handling any challenges, because some things we teach here are not done in NCEA, like vectors and metrics."
Year 12 student Firooze Colaabavala achieved an A* grade in last year's exam, meaning he got a 90 per cent score or above.
"I find Cambridge to be a more pure form of maths than the regular NCEA type stuff, which I quite enjoy and I think most of us do," Colaabavala said.
"It's just a more extended qualification which is really nice to have."
Benjamin White also completed the Year 11 course with an A* grade in 2020, and said would continue with Cambridge Maths until he finished school at the end of next year.
"Cambridge is definitely more challenging than NCEA, but I quite like that in maths," White said.
"It teaches you a lot of stuff that isn't writing and explaining every step of your working, and it's quite good to do a bit more of those fast-paced things. It's good fun."
White said he would study for a tertiary degree "to do with of science" after finishing at Whanganui High School.
"Maths and science go hand in hand just about all the time, so extended maths should be really helpful there."
Troy Brennan, now in Year 13, got an A grade in the 2020 Year 12 exam, something Prasad said was "an amazing achievement".
"Level 1 was quite challenging and level 2 was even more, so I'm hoping this year will be even more of a push," Brennan said.
"I've always liked maths and been reasonably good at it, and it's meant to make sense. Things just work together nicely,
"It's really useful as well because I want to be an engineer in the future. If I follow that path then math is a big part of it.
"If I can have an advanced level of maths going into it, that's definitely an advantage."