Potty Training: Teaching Boys to Pee Standing Up
Don't worry. All little boys ultimately learn to urinate while standing when they go to preschool or see other little boys or their daddies doing the deed. In any case, during potty training, it is best to have your little boy sit rather than stand because you might get lucky and he'll have a bowel movement when he urinates.
But if you are really interested in helping him right now, here's a simple trick you can use: Throw a handful of flushable potty targets, such as Cheerios, into the bowl and encourage him to aim and shoot.