Best thing to do is check out the manual at:
http://www.php.net/manual/
This documents all of the functions and methods that php contains. If you are looking for something MySQL specific, look at:
http://www.php.net/manual/ref.mysql.php
This is a reference for all of the mysql functions and examples of their use. Plenty of help is contained online.
By the way, what school is this? I've never known a school that taught php, that is very interesting... Hope that helps though! Any other questions you can email me by clicking on my name above.
Chris King