This work focuses on the statistical methods used in determining the similarities and differences in the energy and nutrient intake of boarding schools in Croatia, following the seasonal menus as well as the success of the intervention. The intervention implies the application of computers in the weekly diet planning, that are in the accordance with recommendations. Descriptive statistics and regression models were used for the data analysis. Nutritional and energy value for 14 days and the number of servings of basic food groups, for two seasons (spring / summer and fall / winter) was observed. Considering the results where the range of daily energy content varied from 2122 to 3589 kcal / day, as well as the content of fats, that diverged from recommendations because of a large amount of saturated fat - a computer based meal planning was applied (intervention) in order to achieve the menus in accordance with the recommendations and to reduce large swings in the energy content. Additionally, mineral (iron) was chosen in order to follow its contents in the menus before and after the intervention. The use of computer applications has resulted with daily menus with adequate energy and nutrient content that complies with the recommendations and with a higher prevalence of food groups as fruits, vegetables and milk and dairy products. The models showed that the source of iron can be predicted based on the serving of some food groups, but better predictions are gained from different food groups, especially grains, combined with vegetables, fruit or meat intake and not as expected just by meat and meat products.