Throughout the school there are HD TVs connected to computers that show looping slideshows of info, pictures, etc. This is how they work:
The TVs serve as the monitors (via HDMI) for small computers that are located with each TV. We do not use the tuner or other TV functions of the TVs.
The computers run Ubuntu Linux and are set to automatically display a Google-Drive-stored Slides slideshow when the boot up. This alleviates the problem of who maintains the content of the slideshows, as Google Drive allows multiple people to edit the content of the displays - they just need access to the file.
The computers have a single button on their fronts:
If the computer is off, one push of the button will turn it on.
If it's on and not frozen, one push of the button will make the computer shut down.
If it's on and frozen such that one push of the button is not causing a shut down, holding down the button for a few seconds will turn off the computer. Count to 6 and give the button one more push to boot the computer back up.
If there's ever a need to interact with the computers, there is a small wireless keyboard+trackpad velcroed to the back of each HD TV. These keyboards have power buttons. Please replace the keyboard back onto the velcro when it's not being used.