Ok, so this is a tough one. Affect and Effect are commonly mixed up, but once you know the difference, they're not that difficult.
Affect is a verb. For example: Her laziness will affect her grade.
The laziness is actually doing something to the grade. Affect is a verb because it does something.
Effect is a noun. The effect on her grade is that she will fail. With every cause, there is an effect. Because a noun is a person, place, thing or idea, effect is a noun.
I hope that was clear for you all. Good luck!