The purpose of this site is to give you a feel for how a real Moodle using school operates. As a guest you can only view the courses; you can't participate. To have a clearer understanding and some working examples, it's better to use Moodle "in character" so we've set up some accounts already and you are very welcome to log in with them.
The whole site is reset on the hour so feel free to make as many changes as you want. Just don't expect to see them again when you come back another day!