Technology is often portrayed as changing rapidly, even exponentially, and many people have observed unbelievable changes in their own lifetime. This view can make some feel that it is futile to try to teach computing in schools. Some even suggest that children know more about this than adults, so we needn’t bother trying. But what is actually changing, and what are the underlying ideas that are foundational? How can we engage with fashions as they come and go, but avoid...