I need to delete all users and home folders every few weeks

But I need to leave my admin, ard and default accounts untouched.

Is there a terminal command that I can use to delete all stored accounts but leave specified ones alone?

We have several users logging on via Active Directory daily and saving to the home folders the machines will get filled up very quickly if they are not purged every few weeks, at the moment I am having to delete each account from each mac one at a time and it is very time consuming the students are given a 14 day share the deletes anything over 14 days and are told not to use the home folders but of course they still do.