I need to know how I would be able to clean out the trash can of a single "dumb" user every time the MAC is turned on.

Back ground.
OS 10.3x
G3 Mac
Two users configured...
1) Root or Admin (superuser)
2) student (Simple no access to anything but shared folder for files etc.)

The problem is student's keep deleteing items from the itunes area and the trash can fills up and gives system warnings about the trash getting to full ie /tmp 100%....

It would be great if I could create a startup script the deletes the trash for the user and modify the startup some how for this....

I know a little unix but never played with MAC's before

Thanks in advance