If you think about it, programming has a lot it can offer the standard "Three R's" curriculum, for it fosters the application of math and other subjects. If you've ever had to tutorial children, a common whine is "where will I ever use coordinate geometry again?"
Programming also teaches logic and problem-solving skills, and no matter what field you go into, it will require those skills.
Making computer games can also help a student re-enforce other, non-STEM subjects like art, music and English. I recently had a teacher come up to me to ask if I could help her put together a database program to help her 4th graders track the decline of endangered species.