Looking up...
この学校には500人の生徒がいます。
This school has 500 students.
A person who is learning at a school, college, or other educational institution.
生徒たちは教室で静かに勉強していた。
The students were studying quietly in the classroom.
彼女は中学校の生徒です。
She is a junior high school student.
Often used for K-12 students; for university students, 大学生 (daigakusei) is more common.
Use 生徒 for K-12 students and 学生 for university students or adult learners. For example, 中学生 (chūgakusei, middle school student) is a 生徒, while 大学生 (daigakusei, university student) is a 学生.
From Middle Chinese 生徒 (shēng tú, "student"), combining 生 (shēng, "to be born, to live, to grow") and 徒 (tú, "person, follower"). The Japanese usage follows the Classical Chinese sense of a learner under a teacher's guidance.
生徒 is typically used for younger students (elementary to high school), while 学生 is preferred for university students. In formal contexts, it may also refer to disciples or followers of a master/teacher.