BuddyPress.org

Try this:

<li<?php if ( is_page('games') ) {?> class="selected"<?php } ?>><a href="<?php echo get_option('home') ?>/games" title="Games">Games</a></li>

I removed bp_is_page() and replaced it with is_page(), since bp_is_page() is only specific to BP components.

Also I removed the _e and echo references to “Games”. Chances are you won’t be using a translation patch editor.