The brother and sister duo can be found most days at the beach honing their talents and have their sights set on professional careers.
Not ones to shy away from critiquing each other, they believe their rivalry has helped them progress through the ranks and notch up wins on the national circuit.
"I tell her what she is doing wrong," Jonas jokes.
The pair have put in long hours training and mum Ana Axfeldt is often called upon to video their moves.
"The children are very dedicated and determined," she says. "They always want me to film them so they can watch the footage and improve their techniques and manoeuvres."
Jonas started surfing as an 11-year-old, admitting he was a late starter, but says his passion for skateboarding helped.
Elin began surfing when she was nine and loves all aspects of the sport.
"It's so hard to describe. I like the freedom of being in the water and the feeling you get when you are in the barrel or catch a great wave."
At the moment they are coming up with innovative ideas to raise $10,000 to fund the trip to Ecuador.
The Tawharus aren't fortunate enough to have sponsors but that hasn't put the teenagers off - in fact it's made them think of novel ways to increase their profile.
They have made a short clip that appears on The Telecom Foundation givealittle website where people can pledge their support.
The scenes are shot at Mount Maunganui and show Jonas and Elin surfing the break and includes a personalised commentary.
Want to Help?
On the web - www.givealittle.co.nz search Go Ecuador
Garage sale, this Saturday, 7am, 14 Moa St
Yoga class, March 16, at 4pm suitable for beginners. Soma Massage and Yoga Centre, 11 Owens Place, $20. Phone Ana 5757310.