One problem, competing priorities and thirty minutes to find a way forward. Mixed teams must balance cost, performance, and circularity, then make their case in sixty seconds before a winner is chosen. Practise making a real materials trade-off under pressure and turning it into a proposal that would stand up to buyers and investors. • Which material approach would your team choose for a challenge? • Which trade-off would you accept, what evidence would you need, and who must commit first? • Can you make the case in 60 seconds?