Entity Relationship diagram help

[Navya91]

Hi,

I have to draw an ER diagram for assigning classrooms for scheduled courses for university.
A classrom is simply a room within a particular building and all bulidings on campus have atleast one classroom. A classroom is scheduled for a particular time and day or days of a week. If there are at least 15 students enrolled in a class, the class is included in the course schedule. The course schedule assigns a classroom to every course listed.
So, the entities for this case are:
Classroom
Building
Student
Class
Course Schedule
Well, I know the attributes for the student are studentid, name, course name ,classroom no.
I want to know the attributes for each of these entities and their relationships. I am new to this topic and have no clue how to do it?
Please help me how to solve this question.
Thank You

[urtrivedi]

sample data models
http://www.databaseanswers.org/data_models/index.htm

class scheduling
http://www.databaseanswers.org/data_models/student_class_scheduling/index.htm

[Navya91]

Thank You so much for the help.