Introduction: Anaemia is a major health problem in India. Various studies mention poor nutrition knowledge and education as main factors of malnutrition. Aim: This study aims at assessing the effect of nutritional education on iron among school children. Materials and Methods: A cross-sectional interventional study to improve nutrition literacy in schools was undertaken from April 2018 to February 2019. The outreach platform used was Eat Right School program by Food Safety and Standards Authority of India (FSSAI). A study tool employed was data collection using self-developed questionnaire for pre and post-intervention knowledge assessment. School children from Delhi NCR and Mumbai participated in this study. Knowledge intervention was done on 5 key elements related to iron including role, sources, iron deficiency anaemia, iron absorption and knowledge of fortification. Chi-squared test (α=0.05) was applied for comparison. Results: It was found that 54% (n=18,626) of school children studied were in the age group 11-14 years. From 27355 participants who reported the gender, 58.1% (n=15899) were boys and 41.9% (n=11456) girls. Comparison of pre and post-intervention assessment revealed that percentage of students knowing importance/role of iron increased from 27.30% to 59.50%, iron deficiency anaemia from 34.03% to 59.85%, sources of iron from 25.20% to 51.70%, iron absorption from 36.00% to 61.2% and knowledge of fortification from 55.4% to 76.9%. Thus, significant shift (p≤0.001) in all the parameters was observed; improvement in scores ranged from 21.5% to 32.20% with highest increase seen in understanding the role of iron. Conclusion: Results of the study reject the null hypothesis leading to acceptance of alternate hypothesis. The alternate hypothesis highlights the role of nutrition education in improving the nutritional literacy of school children in the area of iron and iron deficiency anaemia. Results of the current study increased the knowledge of children on all parameters related to iron education module. Thus, nutritional literacy is imperative in improving nutritional status and adolescent age-group is the window of opportunity to correct it.