Binocular Convergence

From time to time, I sometimes get bored of school, as most stuednts do. And I have to find a way to somehow pass the time, and this includes staring at pencils oddly, kind of like in the photo below. But appearantly, this is an example of binocular convergence, which is basiclly the fous of both your eyes. And when you put an object very close to your face, and try to focus on it, like in the picture, you can feel your eye muscles straining.