You don't need to be writing fiction to integrate suspense into your work.  In fact, a dose of this tension might be exactly what your essay needs to nail that "A" in class (apart from clean writing, of course, courtesy of your English grammar software).

Of course, you don't need to craft a whole tale of dramatic anticipation to make your writing suspenseful.  Unless you're writing a piece of fiction, you aren't likely to be that interested in concocting a whole tale that rivals the best on-edge novel from Stephen King.  With regular writing, you accomplish the goal of integrating suspense by adding cliffhangers, short bursts of sentences that keep the reader wanting more.

Cliffhangers

You're probably familiar with cliffhangers from movies and TV shows.  For instance, one of the main stars is about to reveal his secret identity when the scene is abruptly cut off, panning over instead to another time line.  It makes you wonder what the secret identity is, how the other characters will react and so forth.  Whatever thoughts spin around in your head isn't really the point - the important part is that it's got you involved.

Writing cliffhangers is pretty much the same way.  You set up a possible scene in a paragraph, but leave its actual resolution in another, drawing your readers in to proceed. Peppered across your text, you'll end up creating drama all throughout your copy, getting your readers more and more involved.

When writing cliffhangers, the best way to integrate them is right at the boundary where you will introduce a new topic.  In many ways, it can be used as a replacement for a regular paragraph transition, one that's more interesting and noteworthy.