Reboot an iPad
A lot of iPad problems can be resolved be giving them a reboot. A proper reboot of an iPad can be achieved by holding the Home Button and Power Button simultaneously for approx 6-7 seconds. The screen will go black during the process but keep holding until you see the white Apple logo appear in the centre of the screen. Let go at this point.
This is known to resolve such issues as;
No WiFi Connection
No Keyboard Connection
Apple Classroom not Connecting to Student Devices