When the pandemic forced schools into remote learning, Washington-area science teacher Rebecca Bushway set her students an ambitious task: design and build a low-cost lead filter that fixes to faucets and removes the toxic metal. Using 3D printing and high-school level chemistry, the team now has a working prototype -- a three-inch (7.5 centimeter) tall filter housing made of biodegradable plastic, which they hope to eventually bring to market for $1 apiece. IMAGES AND SOUNDBITES