I don't want my students to know how many points a question is worth. How can I do this?
You can't do that without hacking the code (or your theme).
In your theme, you should be able to add a style rule something like
.que .info .grade { display: none; }
(You may need to use firebug to get that exactly right.) Alternatively, in mod/quiz/locallib.php, find the line that says
$options->marks = self::extract($quiz->reviewmarks, $when,
self::MARK_AND_MAX, self::MAX_ONLY);
and replace MAX_ONLY with HIDDEN.