The master Lego legends, aged just 15 and 16, will fly to Arkansas in May 2020 to put the skills of their hand-built Lego robot 'Rocky' to the test for the First Lego League.

The Lego League is a competition for upper-primary and lower-secondary school students. Every year, teams of up to 10 students build, program and compete with a robot, while also learning about a modern problem in science and engineering and developing solutions for it.

Rocky is a one-of-kind Lego robot that the siblings designed and programmed themselves with the mission to tackle Australia's landfill crisis.

"Our idea is using a thing called an autoclave, which is like a giant pressure cooker, where all the waste gets cooked and turned into a dry waste which then can be used as a green fuel and can be sorted into plastics and glass to be further recycled," Ben said.

His younger brother Luke said the problem needed addressing before it was too late.

"We originally decided to do this for our project because we know how much of a problem waste really is and that only half of our recycling gets recycled due to contaminants," Luke said.

"We made it our focus because if we don't do anything now it's just going to become too big of a problem to handle."

The Terang College students took out third place in the south nationals, and are one of two Aussie teams heading to America to vie for the top place as world champions against 70 other teams from around the world.

They have been passionate about building and designing Lego ever since they were young.

"We've had Lego for a long time, getting a lot for birthdays and Christmas, then when I first got to high school they ran competitions and I found it so awesome and I've done it since then," Ben said.

"I just find it so awesome being able to build something that can do all different things at the press of a button once it's programmed.

"I would love to do something in designing and building, using Lego on different projects would be awesome. Maybe even become an engineer."

Proud mum Lynne Wickenton said her sons spent 'every spare moment' working on the project.

"I am very proud, I know how much hard work has gone into getting where they are today," she said.

"They work tirelessly, every spare minute they spend on robotics.

"Even when things didn't go their way they kept persevering."

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