An explanatory essay is basically an essay where you describe your thesis where in let's say for example an argumentative, you are fighting for your own personal stand point!
Good example!
Explanatory: The test was given to the kids and 50 percent did well while the other 50 did not, in the article.... etc etc
Argumentative: The test proves that test taking skills are (or are not depending on your stand point) determined on the amount of sleep people get for many reasons, tho some may say... etc
