As somebody who had programming classes (first Pascal and then Java) throughout all my highschool being taught by a Math teacher who never really programmed other than the basics and the textbook stuff... I can tell you that I'm still glad we had the chance. Since day one I already knew more than the material and arguably than our teacher (before Highschool I'd been dabbling with PHP and C programming for web-related stuff as a hobby and as I kept going I was also doing extra stuff on the side while going to school so I never stopped being ahead).
I spent most of my programming classes in Highschool helping my friends and my teacher with stuff they didn't understand, correcting her (my teacher) whenever she got something wrong, no mocking. This kind of experience really made me become a better programmer and mentor for my peers, helped them improve and really enjoy the material (being taught by an enthusiastic peer has a much more positive effect than being taught by a borderline incompetent adult).
Most likely this experience is an outlier case, however I wanted to point out that by simply introducing programming classes is a great starting point towards fostering a more positive environment for the skilled student to thrive and for the less-skilled students to at least pick up something.