The prototype cities on display at February's National Engineers Week Future City Competition in Washington, D.C., featured magnetic levitation trains, fuel-cell automobiles, and other environmentally friendly advances that urban planners have advocated for decades, though these planners were barely a decade old. The 14 participating teams looked at the future through 12-year-old eyes; proposals reflected the range of junior-high temperaments, from convincing to optimistic to prankish. Vulcan, an Icelandic city of the year 3703, has banned cars and draws energy from the ocean. Earth View, a moon colony submitted by a team from Omaha, Neb., is home to "transparent titanium" and the top-ranked Lunar Huskers football team. Marmalade Chunks -- on the Jovian moon Ganymede -- exports marmalade made from an orange-like fruit, since oranges are long since extinct on Earth. Settlers avoid overcrowding by shrinking themselves with a "debigulator." (The physics of the device were sketchy.) Shrink rays aside, concern about environmental collapse and urban sprawl outpaced whimsy during the two-day finals. One team lectured judge and reporter alike that damage to the ozone layer might already be irreparable. The students' intense emotions seemed only more poignant given the competition's corporate affiliates: General Electric, Chevron, Texaco, and 3M.