I third Jare's opinion.
They are simply displaying that they are incapable of modesty and humbleness. In the end an employer would rather higher a decent person as opposed to one who is full of themselves. It is better that you make a few mistakes anyways as you will go into the next test with a goal of improving yourself as opposed to being overconfident. And if you are too used to 100%s then you are not going to cope with college. Not only is it harder to get incredible grades, you throw everyone else who was at the top of their school in one place.
You are doing better than them I bet.
Juggling around school and a job would not be too common at your age, especially for someone doing very well.
Their were very few Asians at our school. We only stereotyped them as smart as a joke. They honestly did not mind. In my grade they were about in the middle of the class.