Match two distinct values from a single column in a joined table

I have three tables:

class: class_id class_name  student: student_id student_name  class_schedule: class_id student_id 

I want to select all the classes where studentA and studentB are in the same class using the student names. I can use a subquery to pull all the classes studentA is in, and then from that subset the classes that studentB is in and that works. That being said, it is terribly inefficient. I have tried a number of solutions including joining the same table twice, once for each value I want to find, but always get an empty result set.

For testing and prototyping purposes I am using sqlite, but will reside on DB2 long term.