I was able to accomplish my goal by adding an index.php file to my child theme based on this one from the Theme Shaper Tutorial: http://code.google.com/p/your-wordpress-theme/source/browse/trunk/index.php.
I modified it as follows:
<?php get_header(); ?>
<div id="container">
<div id="content">
<?php /* The Loop — with comments! */ ?>
<?php while ( have_posts() ) : the_post() ?>
<?php /* Create a div with a unique ID thanks to the_ID() and semantic classes with post_class() */ ?>
<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
<?php /* an h2 title */ ?>
<h2 class="entry-title"><a href="<?php the_permalink(); ?>" title="<?php printf( __('Permalink to %s', 'plasticarmy'), the_title_attribute('echo=0') ); ?>" rel="bookmark"><?php the_title(); ?></a></h2>
<?php /* Microformatted, translatable post meta */ ?>
<div class="entry-meta">
<span class="entry-date"><abbr class="published" title="<?php the_time('Y-m-d\TH:i:sO') ?>"><?php the_time( get_option( 'date_format' ) ); ?></abbr></span>
<span class="meta-sep"> | </span>
<span class="comments-link"><?php comments_popup_link( __( 'Leave a comment', 'plasticarmy' ), __( '1 Comment', 'plasticarmy' ), __( '% Comments', 'plasticarmy' ) ) ?></span>
<?php edit_post_link( __( 'Edit', 'plasticarmy' ), "<span class=\"meta-sep\">|</span>\n\t\t\t\t\t\t<span class=\"edit-link\">", "</span>\n\t\t\t\t\t" ) ?>
</div><!-- .entry-meta -->
<?php /* Microformatted category and tag links along with a comments link */ ?>
<div class="entry-utility">
<span class="cat-links"><span class="entry-utility-prep entry-utility-prep-cat-links"><?php _e( 'Posted in ', 'plasticarmy' ); ?></span><?php echo get_the_category_list(', '); ?></span>
<?php edit_post_link( __( 'Edit', 'plasticarmy' ), "<span class=\"meta-sep\">|</span>\n\t\t\t\t\t\t<span class=\"edit-link\">", "</span>\n\t\t\t\t\t\n" ) ?>
</div><!-- #entry-utility -->
</div><!-- #post-<?php the_ID(); ?> -->
<?php /* The entry content */ ?>
<div class="entry-content">
<?php the_content( __( 'Continue <span class="meta-nav">»</span>', 'plasticarmy' ) ); ?>
<?php wp_link_pages('before=<div class="page-link">' . __( 'Pages:', 'plasticarmy' ) . '&after=</div>') ?>
</div><!-- .entry-content -->
<?php /* Close up the post div */ ?>
<?php endwhile; ?>
<?php global $wp_query; $total_pages = $wp_query->max_num_pages; if ( $total_pages > 1 ) { ?>
<div id="nav-below" class="navigation">
<div class="nav-previous"><?php next_posts_link(__( '<span class="meta-nav">«</span> Older posts', 'plasticarmy' )) ?></div>
<div class="nav-next"><?php previous_posts_link(__( 'Newer posts <span class="meta-nav">»</span>', 'plasticarmy' )) ?></div>
</div><!-- #nav-below -->
<?php } ?>
</div><!-- #content -->
</div><!-- #container -->
<?php get_sidebar(); ?>
<?php get_footer(); ?>