Proper Toilet Etiquette for Boys
Your little boy may have stopped having potty accidents, but that doesn't necessarily mean that he's mastered all the toilet etiquette he needs to know. Proper bathroom etiquette generally refers to keeping private matters private and ensuring that everything is as clean as it was before he started. With a bit of practice, he'll have things down in no time at all.
Once he gets in the bathroom, he needs to focus on the task at hand. A momentary lapse of concentration can have a negative effect on aim. Accidents may happen, so if he does "sprinkle when he tinkles," remind him to "be neat and wipe the seat." He should also always flush and put the toilet seat down.
The bathroom is a private space and the business that goes on in there should be kept private. Though the school might take children in groups, if he's in a situation at home or at a friend's house, they should take turns using the bathroom and resist any urges to show each other what's in the toilet.