🧪 Prototype Build and Test Plan

Teams build a low-fidelity warming-device prototype using foam, fabric scraps, plastic bags, tape, string, and reusable containers, then set up a simple cold-water test with thermometers, cups, and timed observations. They also outline the matching dive-plan draft pieces they will need on their board: air calculations, route map, checklist, and particle-model diagram. Each team records one testable claim about warmth and one safety claim about air use before testing begins.