Despite his average grades, he was considered an overachiever in the class because of his exceptional performance in extracurricular activities.
尽管他的成绩普通，但由于他在课外活动中的出色表现，他被认为是班上的一个成绩超常学生。
She is an overachiever who always strives for excellence, often going above and beyond what is required.
她是一个成绩超常的学生，总是追求卓越，经常超出要求去做。