I understand this issue appears to be just some sort of "high school drama."
But many people take interest in magic during or before their high school years, eventually growing up to become successful and/or influential magicians. This can be seen in the list of Wire artists.
And let's say we have people in high schools who have the potential to become the most creative minds in the field of magic or cardistry. They might develop a distaste for the entire magic community if all they see are kids like the one I've mentioned on the original post, performing poorly and revealing the simple methods behind amazing effects.
Everyone deserves to see magic done well, because that's how performances arts are meant to be done.
I just want to know if I should tell him to stop, or convince him to work harder and practice more.
Your reading too much into this, its your youth and high school mindset.
As said before, this guy just got into this magic business because he saw someone else do it. He is making "mistakes" and if he is interested in doing so he will learn on his own what not to do. or he will simply lose interest and everyone will forget within a week or two's time what it is that he ever revealed.
As i said before, if you want offer him your two cents but its his business.
Do you meddle in someones art work when someone is learning how to paint?
How about in someones first short film? do you steer him into your direction because the way you do it is the "correct" way?
Mike hankins gave you an example of himself. he used to be that kid. he learned.
Let the kid be, focus on your schoolwork and whatever magic you perform at your school.