In my school (which graduated 75 when I graduated), they required some basic computing classes - how to use MS Office and typing (among other things). Back in 2000, that was a rarity... They also offered 2 "programming" classes. One was HTML and the other was VB6. I have to say that while HTML isn't a programming language, it is a lot better than most of the other schools in my area. While I didn't use VB6 in any of my classes in college, having a basic understanding of form and logic definitely helped.
So I have to say that *some* high schools do know what Computer Science is.