Nathan followed a technological process to create a rubbish trap that stops rubbish from floating down the streams, through pipes and into the ocean.
He created a plan, with a diagram and labels
Then he explained how it works! After that Nathan built his model.
He used a metal tray, put holes in them and added handles.
He changed his first plan, because he wanted to use metal instead of wood. He knows that wood becomes rotten and metal is stronger.