As I go from student to student, helping them debug their program, it strikes me that there’s a very simple reason why teaching programming is a help for all students. So many of them have simple typographic errors: three n’s in “running,” leaving out the n in “column,” etc. I give them some hints (often simply saying “spelling error!” suffices) and they stare at the screen intensely until, with a smile, they find the mistake. That’s when I tell them: they’re going to be so good at proofreading their work in all their classes!
There’s probably a good research question there: do students who learn to successfully program apply their proofreading and error checking skills in English and other classes? It’s something I’m going to track with my current students …meanwhile, I’ll just continue to help them develop careful spell-checking and proofreading skills.