Data structure used to store student information

I was trying to design a data structure for student information for one my projects.

If I want to store student data such that some students take Physics, some take Chemistry and some take both.

If I want to know all details of students like name and courses taken etc. which Data Structure and design pattern would be optimal.How to design this optimally.

I was thinking of using B-Tree and not quite sure of what design pattern is ideal.

Any suggestions would help.Thanks.