"4-H groups were soon cratering their neighborhoods and farmers tilling their fields in search of otherworldly harvest. The project surely marks the only official liaison between NASA's Goddard Space Flight Center in Maryland and Pottawattamie County, Iowa's Agricultural Extension; the latter reported being "swamped with samples worthy of a geological museum." A mountain of would-be moon material was submitted for testing at NASA's Ames Research Center in California. Promising specimens were crushed, examined by microscope and spectrograph, then probed for evidence of the superheating and cosmic-ray activity characteristic of exposure to space and atmospheric entry to Earth. Yet the project's final harvest, including smokestack clinkers (bits of residue blasted aloft during burning or smelting) and even fossils, produced nothing extraterrestrial. So the effort, after running just short of a year, ended in March 1965, with each sample returned to its sender, along with a letter of thanks."
More: Searching for Moon Rocks in Iowa, Air & Space