Since 2005, the Dietary Guidelines for Americans (DGA) has recommended that whole grains comprise at least half of total grain consumption. This study used nationally representative food consumption datasets (spanning 1994-2018) to examine trends in whole-grain intakes before and after the establishment of this recommendation. Trends were examined by age group and food source; that is, food purchased at grocery stores and other retailers to be eaten either at home or away (as a brown bag lunch) versus food purchased at restaurants, fast-food establishments and similar sources, and schools. Across the entire time period studied, the diets of older U.S. consumers (65 years old and over) were richest in whole grains on a per-1,000 calorie basis--but only among children (2-19 years old) did intakes, measured on a per-1,000 calorie basis, increase during 1994-2018. Multivariate analyses indicate this finding was largely attributable to changes in whole-grain consumption from foods obtained at school. Since 2013 (following the implementation of new standards requiring school meals subsidized by the U.S. Department of Agriculture (USDA) to offer more whole-grain-rich foods), approximately one in two children who ate school food consumed whole grains on the survey day, whereas previously, fewer than one in five of such children consumed whole grains. Children who selected whole grains when eating food obtained at school also ate larger amounts, measured as ounce equivalents consumed per 1,000 calories, with 2013-18 levels more than double those of 1994-2010.