HABTM - How do I do a select box for this?


I’ve got several habtm’s working fine in my app but have been having
trouble with a new twist: imagine an app that tracks students and
courses that they’re taking. So there’s a student Class and a course
Class, and the tables also, and a students_courses table. This stuff I
have down cold.

The problem was I wanted a form that allowed associating a student with
up to three courses, each individually selected from a drop-down select

Student: John
Course 1: (select box)
Course 2: (select box)
Course 3: (select box)

I tried the following for my select box code in my view (this is
pseudo-code, I don’t have the source with me):

<% select :student, :course_id, Course.find(:all) %>

The error I’m getting is with the second parameter above. I think I’ve
got that wrong. Is there any way to do what I’m doing? I think the
problem is that I don’t understand how to modify a collection of many
courses when I’ve got three separate select boxes. Thanks very much.