When I was younger, the "logo" computer language was well-regarded for education of the young.

It is now a JavaScript platform:

https://turtlespaces.org/

Historical background may be helpful:

https://en.m.wikipedia.org/wiki/Logo_(programming_language)

Smalltalk, as the founding language for object-oriented programming, was originally targeted at children.

https://en.m.wikipedia.org/wiki/Smalltalk

I don't think any operational versions still exist.