It wasn't in the Netherlands. A graphical calculator was required for math and many kids learned at least some programming by creating their own little programs to cheat in tests. Also, you could get code for games and then program them. The newer ones with USB cables made adding games much easier though.
The word you're looking for is "serial port."
Neopets allowed "pet pages" containing HTML when I was 10 years old, and this was my first foray into programming.
There's this huge tribal knowledge built up around copy-paste CSS hacks to enable things like tab navigation all on one page with no JS. It's actually pretty wild some of the stuff these folks do, especially since almost none of them have any technical knowledge and it's all trial-and-error and sharing what works through the forums.
The amount of hackery they do for their forum guild pages (hosted as pet pages) and such almost blows my mind more than the fact that Neopets is still around and somewhat active after all these years.