Huge Fonts randomly

Hi,
Since the upgrade to iOS 6 one of the iPhones in my family now will show huge fonts out of nowhere. So huge only a portion of my screen is visible and then nothing can be done, only a reset (home+power button) will fix the issue. It happens on its own too, even while in lock screen, you go try to use it and you see a small part of the wallpaper displayed and sometimes part of the notifications, the phone isn't frozen or anything but any button you can get to or the slide bar to unlock are not visible so can't use it, must reboot

Any ideas? I checked accessibility and it was all turned off.

Thanks

I will try both suggestions above. It's the entire screen that is zoomed in. I didn't know there was such a zoom feature on the iPhone. This device is not here right now but I will try it tonight. Thanks.

I guess I should have accessibility turned on, I read that twice and didn't see it I looked and Large Text was off but Zoom was on. So that was it, a 3 finger double tap would zoom and my mom was activating that w/o knowing and complained she couldn't use the phone after that. So I turned it off now and all is good.

Thanks everyone for the tips.