(Some phones, like Samsung Galaxy devices, will have a "More" option instead of the three-dot button.) Tap Settings, then Call Blocking. You can search your contacts to find a number to block.

If you press the "Emergency call" button on a phone that's locked by passcode, you'll get a dialer. Dial a fake number, then as soon as the red button allowing a hang-up appears, press the sleep ...

To unlock a Boost Mobile phone, you'll need to call the Boost Mobile Customer Care line at 1-888-266-7848 and request it.

These days, making an emergency call is a more complex operation than in the past, as children will often have to find and unlock a cell phone to do so.