Problem With Metasploit

I am trying to demonstrate how SELinux can stop zero day attacks and i am using Metasploit with the following exploits:
phpbb_highlight
awstats_config_dir
wordpress

I have installed the vulnerable applications.However, when i try exploiting them, nothing seems to happen.It just brings back the previous prompt.What could the problem be??

Well can you give us the things you enter in the metasploit CLI?

Also, if you cant handle a tool. its problairy not right for you.