To improve the dietary offering in schools, the French authorities published recommendations on nutrition in 1999, which were then revised in 2007. The aim of the present study was to assess the nutritional offering in secondary school meals and the extent to which the recommendations promote balanced nutritional offerings. In 2005, a national survey was conducted on a representative sample of secondary schools, either administrated by the Ministry of Education (ES) or the Ministry of Agriculture (AS). Information on school-catering organisation and twenty consecutive meals was collected from each of the 707 secondary schools surveyed. Nutritional composition was estimated according to the French food composition database. Univariate and multivariate analyses were used to investigate the impact of food-group frequency guidelines (FFG) on nutritional offering. It was found that 15 and 26 % of ES and AS schools, respectively, had high compliance with the FFG, at lunch. Macronutrient content was unbalanced in ES school lunches in which 42·8 % lipids, 21·5 % proteins and 35·7 % carbohydrates contributed to the energy. Nevertheless, proper offerings in Fe, Ca and vitamin C content were observed. In addition, a lower offering in lipids and a higher offering in proteins, Ca, vitamin C and Fe were found when the FFG were applied (P < 0·001). Similar results were found for AS schools. This paper confirms the effectiveness of FFG in providing nutritionally balanced school meals. However, others measures such as nutrition promotion and actions to improve children's food habits have to be introduced to make the recommendations more effective and easier to understand.