registered subject; course
Refers to a subject or course that a student has officially registered for, typically at a university or school.
My registered subjects this semester are economics and mathematics.
Registration for courses is until next week.
科目 is a general term for a subject or course, while 履修科目 specifically means a subject one has registered for.
履修 is the act of taking or registering for a course; 履修科目 is the course itself.
Compound of 履修 (registration, taking a course) and 科目 (subject, course).