What is the best way to customise the standard wordpress custom post listing layout. To be specific, I am trying to add a subheading just below the Lessons / Create New Lesson button but before All (0) | Trash (1)
Is this possible with just a wordpress plugin or i have to modify core file OR maybe create a theme.
If it's possible, how much of this page is customizable by a plugin.
I would prefer a plugin solution.