To run a Moodle quiz on a RasPi, all that is required is that the user logs in using a browser to the school server hosting that quiz. This could be set up with its own login just for this machine so it can only be accessed via the RasPi in the foyer for instance. The RasPi needs nothing more than a browser as everything else runs on the server.
To set up the RasPi as a Moodle server to run a quiz is overkill when there must be some lighter quiz programs available.
Nevertheless I do hope that the RasPii either come with Apache, PHP, MySQL pre-installed or with the ability to run LAMP (which installs all three). This will then allow teachers to teach how to make web apps and for students to learn how three/four very different scripts/languages use their respective strengths to interact (html, php, css, sql).
You will be able to install all of those pretty easily, even if not there as standard. sudo apt-get install is your friend. Having them as standard fills up the SD image when there are probably more important things to have there for the purpose of the Raspi.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
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