Do you playing video games after school affect a students grade

No, exercising something you enjoy does not affect a student's grade, if it is controlled.

Explanation:

Playing a couple of hours a day (1-3 MAX) will not affect a student's grade, but excessive playing will affect their grade negatively, as the video game will stay on their mind unconciously (most of the time) which will distract the student and prevents the student from thinking straight, regarding the fact that it could cause eye damage, and increases the chances of epilepsy.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.