Make News on Front Page viewable to Teachers only

In /index.php, look for case FRONTPAGENEWS:

case FRONTPAGENEWS:
if (isteacherinanycourse()) {
if ($SITE->newsitems) { // Print forums only when needed
require_once($CFG->dirroot .'/mod/forum/lib.php');

if (! $newsforum = forum_get_course_forum($SITE->id, 'news')) {
error('Could not find or create a main news forum for the site');
}

if (isset($USER->id)) {
$SESSION->fromdiscussion = $CFG->wwwroot;
if (forum_is_subscribed($USER->id, $newsforum->id)) {
$subtext = get_string('unsubscribe', 'forum');
} else {
$subtext = get_string('subscribe', 'forum');
}
$headertext = '<table width="100%" border="0" cellspacing="0" cellpadding="0"><tr>'.
'<td><div class="title">'.$newsforum->name.'</div></td>'.
'<td><div class="link"><a href="mod/forum/subscribe.php?id='.$newsforum->id.'">'.$subtext.'</a></div></td>'.
'</tr></table>';
} else {
$headertext = $newsforum->name;
}

print_heading_block($headertext);
forum_print_latest_discussions($SITE, $newsforum, $SITE->newsitems);
}
}
break;

The lines in red are the lines you'll need to add.

Moodle 2.0 It appears that this tip will not work in Moodle 2.0 - you will get an error message saying

 "Function If (isteacherinanycourse()) is removed, use Capabilities instead".  

This implies that Moodle 2.0 allows you to set that as a Role Capability in the Front Page. To accomplish this, you will need a good understanding of Capabilities in Moodle 2.0.