VGA connectors can be found on all the wall mounted boxes for ceiling mounted projectors. Most computers either have this port or can be adapted to connect to this type of port.
HDMI ports can be found on chrome books and will be available on the wall mounts in the future. These can also be adapted to VGA with adapters that can be found in your building's media center or by contacting the technology department via the helpdesk.
Mini DisplayPort is the port type that can be found on the Apple computers used by the district. Each room should be outfitted with a dongle like the one pictured to allow you to project what is on your laptop to the projector.
If you connect your computer to the projector and only see your background on the big screen it means that your display is not being mirrored (duplicated) to the projector.
On a Mac to resolve this press the Command+F1 keys on your keyboard.
On a Windows computer press Windows+P and a set of options will appear on the screen. Continue holding Windows and tap P until the option you want (mirroring/duplicate) is selected.
If you have issues that are not covered by the documentation please visit the Helpdesk.