These are Turnip O' Lanterns. Turnips are somewhat more tricky to carve than are pumpkins, as pumpkins are inherently hollow, and somewhat soft besides. Turnips, of course, are neither. Turnip-carving is definitely something you should not attempt unless you are fairly adult-ish, non-clumsy, and are using a great deal of caution. Please try to aim the knife away from you, so that you don't inadvertently kill yourself. That would be bad, and you might be upset with me if you survive. I'd also recommend not burning a candle in one of these indoors. That really stinks. My parents like the taste of turnip, but they couldn't stand the stench of burning turnip. I assure you, this is a far better use of turnips than actually eating the wretched things.

After carving complicated faces into small turnips (which, in case I didn't emphasise this enough earlier, are extremely solid and not conducive to this), pumpkins are an absolute joke -- completely unchallenging. I understand peppers are also quite nice, and look spectacular with a candle inside, but they're presumably even easier than pumpkins.