我来补充一下吧
President of Students’ Union
或
President of Students’ Council
http://zh.wikipedia.org/wiki/%E5%AD%B8%E7%94%9F%E6%9C%83华文版本
学生会
维基百科，自由的百科全书
学生会 是社会组织，是会所组织，成员主要是学生，顾问可能有教师、校长、前会长、校友、律师、会计师等。
其内部架构通常有有会员、干事或会长、ㄧ级干部、秘书、外事公关、会刊出版、会员福利、财务、总务等职位。
英文版本
http://en.wikipedia.org/wiki/Students%27_unionStudents' union
From Wikipedia, the free encyclopedia
A students' union, student government, student senate, students' association, or guild of students is a student organization present in many colleges and universities. In the latter, said organization is often accorded its own building on the campus, dedicated to social and organizational activities of the student body.
Many students' unions are run by students for students, independent of the educational facility. The purpose of these organizations is to represent students both within the institution and externally, including on local and national issues. They are also responsible for providing a variety of services to students. Students can get involved in its management through numerous and varied committees, councils and general meetings, or become one of its elected officers.
http://en.wikipedia.org/wiki/Student_councilStudent council
From Wikipedia, the free encyclopedia
Student council is a curricular or extra-curricular activity for students within grade schools around the world. Present in most public and private K-12 school systems across the United States, these bodies are alternatively entitled student council, student government, Associated Student Body, Student Activity Council. Student councils often serve to engage students in learning about democracy and leadership, as originally espoused by John Dewey in Democracy and Education (1916).
参考资料：http://en.wikipedia.org/wiki/Students%27_union