Something different for kids in Spain and kids in the United States is that school is structured differently as far as grades.
The structure and ages are the following:
Infantil / Daycare (0-6)
Primaria / Elementary and Middle School (6-12) *
Escuela Secundaria o La eso / Junior High and first two years of high school (12-16)*
Bachilerato OR Formación Profesional / second two years of high school or trade school (16-18)
Universidad / University (18-22)
* means that these years of schooling are mandatory
For breakfast, the children generally eat something light like a piece of fruit, yogurt and some breakfast cookies or toast.
For lunch, they typically have a sandwich and some veggies and fruit.
For snack, they usually have some bread and meat or cheese.
For dinner, they usually have some type of meat or pasta dish and vegetables.