LevAryehBoy: Most WiFi networks are password protected. Unless Yeshuruns kids are walking around town looking for free WiFi, the tablet stays in the house so it can only connect to the house network. Or not, as the case may be.
Yeshurun: To permanently disable the WiFi on the tablet there is no solution. It’s possible, but it requires a decent level of computer expertise. You will need to gain root access and uninstall the network drivers, a tricky task that may or may not permanently break the tablet.