This is such a weird thing to read. You try to project your ideas on the kids, thinking that is the best thing to do. Let them be.

I learned Linux when I was like 13 or 14 and not because my father told me. He didn't know much about computers in early 2000/late 90ties.

The curiosity, the desire to learn, the need to set up my own isp, the need to start to make money, the curiosity of how html, php and other stuff worked let me to Linux.

Teach them how to be curious and feed that curiosity, the rest will happen.

And if they choose Mac over Linux, just get of their way, otherwise they will rebel.