PHP\\'s equivalents to ASP
Request.QueryString(\\"VarName\\") = $HTTP_GET_VARS[\\'VarName\\']
Request.Form(\\"VarName\\") = $HTTP_POST_VARS[\\'VarName\\']
PHP also does a simple variable for you so in both of the above, instead of using $HTTP*VARS[\\'VarName\\'] you could just use $VarName. Similar to ASP\\'s Request(\\"VarName\\") simplification.
BG
<a href=mail.php?InformStudents=\\"$SCHEDULENUM\\">Inform the students</a>
On the mail.php page $InformStudents would hold the value from teh query string.