Jasmine Votano hopes that being plastered on billboards across Europe in her knickers and bra will show the girls she teaches that you do not have to be size 8 to be proud of your figure.
The 25-year-old art teacher at a London secondary school stars in the latest advertising campaign for Dove, the beauty products company.
"The nature of being a teenage girl is to worry about your weight," she said.
"And with so many different personalities, you get girls questioning their body images, as they are not confident with who they are.
"That is why it is so nice to see real women like me showing that we are confident with our bodies without having to be a size 8 supermodel.
"I have learnt that faddy diets do not work. You should just eat healthily and accept the size you are." Miss Votano, who is a size 16, said that staff at her school, which she did not wish to name, had been excited and supportive of her new-found fame.
"I did not give anyone a chance to warn me against it as it happened very quickly. I was feeling a bit low at the time and thought bugger it," she said. "My motto is to have no regrets and I knew if I didn't go for it I would always wonder 'what if..?'.
The question most people have asked is how I felt being photographed in my knickers and whether I was nervous or embarrassed. But to tell you the truth I did it on a whim."
A Dove spokesman said: "The pupils have reacted very positively. They all admire her confidence."
Heather March, who cast Miss Votano, an Australian, in the advertisement, said: "Obviously Jasmine looked right, but it was her personality first and foremost. She is really bubbly and fun.
"She is certainly brave. I do not think I would have done it. I imagine she is a very popular teacher. If it had been one of my teachers I would have thought she was really cool."