depending on age a child needs about 1400-3000 calories per day. the bulk of which should be eaten in the early part of the day when you are most active. 400-800 is not enough for that.
the official US guidelines for school provided lunch range from 550–850. that's a bit lower than i would choose based on daily needs especially for older kids. breakfast and lunch should be more than 1/3rd each. dinner should be less than 1/3rd.
i am from austria. a sandwich here is considered a snack. not a meal.
3 meals averaging 600 calories plus a snack is completely reasonable. A sandwich is a meal. I don’t know what kind of sandwiches you’re eating in Austria but I don’t think it’s the same as me.
the official US guidelines for school provided lunch range from 550–850. that's a bit lower than i would choose based on daily needs especially for older kids. breakfast and lunch should be more than 1/3rd each. dinner should be less than 1/3rd.
i am from austria. a sandwich here is considered a snack. not a meal.