Help with Crontab and Scripts

I'm trying to create a crontab that runs every hour and runs a script in my $HOME/bin directory.
Everytime it goes to run it I get this mail.

Message 14:
From root@xx.xxxx.edu  Thu Apr 12 14:03:01 2012
Return-Path: <root@xx.xxxx.edu>
X-Original-To: bbowers
Delivered-To: bbowers@xx.xxxx.edu
From: root@xx.xxxx.edu (Cron Daemon)
To: bbowers@xx.xxxx.edu
Subject: Cron <bbowers@xx> $HOME/bin/helloworld.sh
Content-Type: text/plain; charset=UTF-8
Auto-Submitted: auto-generated
X-Cron-Env: <SHELL=/bin/sh>
X-Cron-Env: <HOME=/home/IT-43AR-M3306/bbowers>
X-Cron-Env: <PATH=/usr/bin:/bin>
X-Cron-Env: <LOGNAME=bbowers>
X-Cron-Env: <USER=bbowers>
Date: Thu, 12 Apr 2012 14:03:01 -0700 (PDT)
Status: R

/bin/sh: /home/IT-43AR-M3306/bbowers/bin/helloworld.sh: No such file or directory

&

What does this mean? And how come it isn't working?

This is my crontab:

30 * * * * $HOME/bin/helloworld

This is my script:
#!/bin/bash
echo Hello World

Thanks in advance

You forgot the sh:

30 * * * * $HOME/bin/helloworld.sh

in my post. I do have the .sh
Sorry, my mistake

Try using the full path to your script instead of the value of HOME.

If the above didn't fix it, please post the output from the following two directory lists:

ls -lad /home/IT-43AR-M3306/bbowers/bin
ls -lad /home/IT-43AR-M3306/bbowers/bin/helloworld.sh