# query_posts = [_your_doing_it_wrong][1]

as soon as you throw in that nasty query_posts you are killing off all the global variables and your paging will not work.

change:

     query_posts( array( 'post_type' => 'fieldtrips', 'fieldtripcategory' => 'elementary-school-aquifer', 'order' => 'ASC', 'posts_per_page' => 1 ) );
                  if ( have_posts() ) : while ( have_posts() ) : the_post();


to:

 

 

       $my_query = new WP_Query( array( 'post_type' => 'fieldtrips',
                                        'fieldtripcategory' => 'elementary-school-aquifer',
                                         'order' => 'ASC',
                                         'posts_per_page' => 1
                              ));
                      if ( $my_query->have_posts() ) : while ( $my_query->have_posts() ) : $my_query->the_post();


Also remove the wp_reset_query.


  [1]: https://wordpress.stackexchange.com/q/50761/251