Furniture should be designed to serve a purpose. Learners could investigate areas around the school or at local businesses that could use something better or more functional. Tired of those old plastic chairs on the coffee shop patio? Maybe your learners could design, manufacture, and install a new set of comfortable chairs meant for outdoor use? Do learners wish they had variable-height desks in the classroom? Maybe they can design, engineer, and manufacture their own for class use? Will it be a hand-crank design, or electric, or jet-powered? Who knows?