Helen Candy, Paul Canning and Chris Collins all chose to do a module as undergraduate ambassadors.
For Candy, who was reading chemistry at the University of Southampton, it was a way of dipping a toe in the water. "Teaching is always something I'd considered, but I was in two minds whether to go straight into it from university."
Canning, who was studying physics at the University of Surrey, had also thought of teaching. "But it gets a lot of bad press, which put me off. I thought this was a good opportunity to have a try without commitments."
Collins, studying maths at King's College London, simply wanted to widen his experience: "I thought it would expose me to the real world, rather than just sitting in lectures and seminars."
Unlike most students, Candy had had some previous experience. "When still at school, I used to do in-class support. In sixth form, I helped with science lessons for the lower school. And I'm a Guide leader, so I'm used to dealing with ten to 15-year-olds."
Not everyone was so confident. Canning admits to having felt nervous about the school he was linked with. "I knew the area, so I knew it wasn't going to be a cakewalk."
He started with pupils in a year-eight class with a reputation. "When I told people which my first class would be, they were amused. It was unsettling. There were three pupils in the class who were banned from doing practical experiments. They were squirrelled away in a corner doing book work." What they'd done to merit the disqualification, he doesn't know.
All three undergraduates enjoyed themselves. "A really good experience," Collins says. "And I've told friends who are still at university that I recommend it."
Canning agrees, though he was surprised at how much preparation it takes to keep pupils' attention for an hour. "Because the school was doing International Baccalaureate rather than A level, some of the wave physics covered wasn't stuff I'd done. So I had to dig out textbooks and start learning from scratch."
It's impossible to know if the students succeeded as role models, but they were conscious of their ambassadorial status. Collins notes that some of the older pupils had a very negative view of maths. "And they didn't hold their tongues when it came to telling me so. Maths has a bit of a stigma as an uncool and geeky subject. I did what I could to put it in a positive light."
Do the students feel they acquired transferable skills? Yes, says Candy.
"It really enhanced my talents in presentation and catering for different audiences, and also planning things in advance."
Collins agrees: "Trying to communicate ideas to kids is not easy. I had to come up with a project for six or seven of them and then lead them through it. And as part of my assessment, I had to do an oral presentation on the work as well as a written report." He says his experience has stood him in good stead when applying for jobs that demand evidence of initiative.
So what of the future? Having em-barked on a doctorate in engineering, Canning won't be teaching - for the present. Candy will do so when she's completed an MSc in forensic engineering at the Royal Military College of Science. Collins had never thought of becoming a teacher, and he has not changed his mind. "But I've got a far greater appreciation of just how difficult it is. I went into it thinking it's an easy option. I came out knowing that that's completely inaccurate. It's no mean feat standing in front of 30 14-year-olds who've got no enthusiasm for maths and trying to stir up some interest."