Translation:The girls eat all their breakfast.
"Le ragazze" is feminine, so "the girls". Some masculine forms can include girls, but feminine forms only apply to females. Also, "ragazzo / ragazza" seems to apply more to adolescents than children.
The standard translation for "the children" would seem to be "i bambini", or "i figli" (referring to somebody's children).
As far as I can see, breakfast is generally "colazione" and lunch is usually "pranzo", but that "colazione" is also sometimes used instead of "pranzo", in which case breakfast is referred to as "prima colazione"