Nathan:
From what you described, this is what it sounds like your system is supposed to do:
Create an object of type RegistrarSimulator, which creates a number of objects of type Clerk (based on user input) when instantiated.
Run each Clerk as a
thread (using the run() method).
Each Clerk will associate itself with a Student object (which are collected in a ConcurrentLinkedQueue object).
Each Clerk will print a message out to the console which states "Clerk
m is serving Student
n".
I believe what you need to think about is how you would go about associating a Student with a Clerk. Once you've figured that out, doing the toString() method becomes trivial.
John.