Implementation of updated nutrition standards for school meals began during school year (SY) 2012-2013. The standards were designed to improve the nutritional quality of the meals and their consistency with the Dietary Guidelines for Americans. To assess the nutritional quality of school lunches and breakfasts after the updated standards were in place and compare it with the nutritional quality of the meals before the updated standards. School menu data were used from two cross-sectional, nationally representative studies of schools participating in the National School Lunch Program during SY 2014-2015 (School Nutrition and Meal Cost Study) and SY 2009-2010 (fourth School Nutrition Dietary Assessment Study). The analysis used 1 week of school menu data from 1,206 schools at lunch and 1,110 schools at breakfast for SY 2014-2015, and 884 schools at lunch and 802 schools at breakfast for SY 2009-2010. Healthy Eating Index 2010 scores were estimated. Descriptive analyses were conducted to estimate mean Healthy Eating Index 2010 total and component scores for school meals. Scores are expressed as a percentage of maximum possible scores. Two-tailed t tests were used to assess differences in scores before and after updated standards were in place. Total Healthy Eating Index 2010 scores for school lunches and breakfasts increased significantly after the updated standards. Between SY 2009-2010 and SY 2014-2015, the total score for school lunches increased from 58% of the maximum score to 82%, and the total score for school breakfasts increased from 50% to 71% (P<0.05). For both meals, component scores increased by more than 20 percentage points for whole grains, refined grains, and empty calories, as well as for greens and beans for lunches and whole fruit and sodium for breakfasts. The updated nutrition standards for schools meals significantly improved the nutritional quality of the meals and their consistency with the Dietary Guidelines for Americans.