Comic Sans

 Secret tip for the crafty students who enjoy cutting corners

[SPOILER=I'm serious, don't go spreading this around now, folks. This beauty works with almost 100% certainity]
[SPOILER=It'll really help when you're in need of a boost in length, without having to change the font]

 The longer your paper is, the better it works usually

Using Word, Find All + Highlight (this is important) every period (".") in your paper. With all periods selected, increase their size slightly (12.5-13).

Repeat for all punctuation marks, such as commas and apostrophes.

Try it out. It's like magic.

Only way I've ever seen this method detected was if the teacher knows specifically to look for it. Or if they have REALLY sharp eyes. Personally, I've never been discovered, nor have the few people I've shared it with. It's always risky being a cheat, but that's the fun of it.