Trouble populating drop-down from DB


What I Have: I have a form that a user enters information in. That
information is stored in a DB.

What I Want: I want to allow the user to edit/update that information
-you know CRUD

My Problem: Everything is good until I try to populate the select list
in the edit form. I do not know how to populate the list with the
pre-defined options while having the user's previous selection

Code example or links to tutorial would be useful.

Thanks in advance -- K

----The Code----


class Page < ActiveRecord::Base
  belongs_to :user


     ["History", "history"] ,
     ["Humanities", "human"],
     ["Life Sciences", "life"],
     ["Engineering", "eng"],
     ["Social Sciences", "social"]

validates_presence_of :file, :title, :template

class AdminController < ApplicationController

def create_page
    @page =[:page])
    @page.user = User.find_by_id(session[:user_id])
    if and[:notice] = "Page #{@page.title} was created"
      @page =
      redirect_to( :action => 'index')

def edit
    @page = Page.find(params[:id])

  def update
    @page = Page.find(params[:id])
    if @page.update_attributes(params[:page])
      flash[:notice] = 'Page was successfully updated.'
      redirect_to :action => 'list_pages'
      render :action => 'edit'

<%= start_form_tag :action => 'update', :id => @page %>

                <label for="page_title" >Page Title:</label>
                <%= text_field 'page', 'title' %></p>

                <label for="file_name" >File Name:</label>
              <%= text_field 'page', 'file' %></p>
                <label for="template" >Template:</label>

            <%= submit_tag "Edit Page" , :class => "submit" %>
       <%= end_form_tag %>