It is a stark change for computer science, which for decades was treated like a stepchild, equated with trade classes like wood shop. But smartphones and apps are ubiquitous now, and engineering careers are hot. To many parents — particularly ones here in the heart of the technology corridor — coding looks less like an extracurricular activity and more like a basic life skill, one that might someday lead to a great job or even instant riches.

The spread of coding instruction, while still nascent, is “unprecedented — there’s never been a move this fast in education,” said Elliot Soloway, a professor of education and computer science at the University of Michigan. He sees it as very positive, potentially inspiring students to develop a new passion, perhaps the way that teaching frog dissection may inspire future surgeons and biologists.

But the momentum for early coding comes with caveats, too. It is not clear that teaching basic computer science in grade school will beget future jobs or foster broader creativity and logical thinking, as some champions of the movement are projecting. And particularly for younger children, Dr. Soloway said, the activity is more like a video game — better than simulated gunplay, but not likely to impart actual programming skills.