To her pupils, she's still Miss O'Sullivan, despite her high-profile romance with RTE star Ryan Tubridy.
Yesterday, the former Rose of Tralee Aoibhinn Ni Shuilleabhain was hoping students were paying attention as she highlighted the importance of healthy eating during the stressful exam period.
Aoibhinn, who has been working at a mixed school in Tallaght, Dublin, revealed her students pay no heed at all to the publicity surrounding her new romance with Tubridy.
"I've been teaching there for two years now, the students are great they are really hard workers, they are great in class. I'm just simple Miss O'Sullivan," she said.
Over the past few weeks, the student teacher has been busy studying as her boyfriend hit the spotlight after was offered the chance to take over the helm of the 'Late Late Show'.
Yesterday, as she launched www.brainfood.ie ahead of the impending school exams, she said the announcement that Tubridy would be taking over the 'Late Late Show' was "great news".
"It was a surprise, I'm delighted for him and hopefully it will go very well for him," she said.
Last summer, Ms Ni Shuilleabhain filmed a traditional music series for RTE called 'The Reel Deal' which will air from Friday, June 12.
"I never had any plans to get into media, it all happened by accident because of the Rose of Tralee," she said.
The former competition winner will be returning to the Co Kerry town later this year for the 50th anniversary of the Rose of Tralee.
Yesterday, the teacher launched the website www.brainfood.ie, set up by fish foods products specialist John West Foods, and a new study probing students' eating habits.
Female students are more likely to snack and indulge in junk food than male students during intense studying, according to the new survey taken among 550 students and mothers of students studying for exams.
Around 68pc of teenage girls tend to snack while studying, compared with 57pc of males.
However, female students generally eat more healthily than male students, with teenage girls opting for tea, fresh fruit, juice, yoghurt and crackers, while boys opt for crisps, soft drinks, coffee and muffins.