Add Multiple users

All,
I want to add about a two hundred users to a group to a network, and delete another group (once a year for school kids). I was wondering is there a script I can use, that will take all usernames from a DB or comma separated list (I will ensureall usernames are unique), and geneate a new account for a specific group, and dump the auto generated passwords to a tempory file on the admin account, possibly even an encrypted file. I dont like the thoughts of adding new users by hand. Then the kids may be prompted to change the password the first time they log in.
Kind Regards,
Shane