gistfile1.php

<?php

// This is a module method. Use it like so... 
// {exp:module_name:class_achievements course_url_title="{segment_3}"}
public function class_achievements()
{
	// Course is a model I created. findUrlTitle() is an inherited static method
	if(!$course = Course::findByUrlTitle($this->param('course_url_title')))
	{
		// If no course is found, return the noResults() method.
		return ChannelEntriesParser::noResults();
	}

	// Achievements is another model that is related to courses. Course
	// has a method name achievements to fetch these related models.
	if(!$achievements = $course->achievements())
	{
		// And if no achievements, return noResults() method.
		return ChannelEntriesParser::noResults();
	}

	// If all is successfully, return the related achievements as a Channel Entries loop
	return $achievements->entries();
}