I disagree with the assertion that students should be studying the required same national curriculum before they get into college.
Firstly, when a student is forced to study some certain subjects that they are not interested in, they might lose their interest in their study. Suppose, a student is passionate about astronomy and love studying Physics, mathematics, etc. But if a nation require him to study chemistry, biology, or subjects related to the political history along with physics, mathematics, she/she might lose interest in study. Besides preparing himself for chemistry, biology, etc. might have a bad effect in his preparation for physics, mathematics, etc.
Secondly, the more time the student, mentioned above, will spend studying subjects that are not related to his or her interested field, astronomy, the less time he or she will have for studying subjects that are related to his interested field. That might lead them to know less about their interested field.
However, there are some certain subjects everyone should study. In this case, I believe, it will be good for everyone if the nation require all the students to take those mandetory subjects along with their favourite subjects related to their interested field.