Newbie ksh script help

I need a ksh script that will make tar files of a list of directories. my problem is that I need a single tarball for each directory. the tarball needs to have the same name as the directory with the .tar.Z extension.
I'm thinking I need to make an array with the names of the directories and then feed each of them through tar, but I'm not sure of how to do this.

In case you're wondering why I need this, each directory is a separate job. Each job is tarred by itself and then when i have enough to fill up a dvd, i backup.

thanks

thanks anyways, figured it out with a for loop

#! /bin/ksh


for foo in $(ls);do
if [[ -d $foo ]];then
tar -cfZ $foo.tar $foo



done