Another case where words that are normally interchangeable are counted wrong if you choose the one the translator did not choose. Pupil and student should be interchangeable. Also "foods" is simply not used in standard English.
The meals of the pupils....the student's food...this is a more understandable statement. Second food and meal in english can be considered different things. I go to the store to get food to make meals.
Food is usually a non count noun in English, especially in this sort of construction. There are many different foods available is okay, but I'd tend to phrase it as there are many different kinds of food. Explaining why I'm reporting this.