A keyboard is configured to protect the display, or screen, and optionally the housing of a mobile computing device, such as a tablet computer, while the mobile computing device is not in use. When positioned over the display of a mobile computing device, the keyboard may provide protection without substantially increasing the thickness or other dimensions of the mobile computing device. The keyboard may also include a slot for orienting the tablet computer or other mobile computing device in a working orientation. Systems including assemblies of a keyboard and a mobile computing device, such as a tablet computer, are also disclosed, as are methods for using keyboards with tablet computers and other mobile computing devices.