While entertaining, I think the PB&J demo is more like "clickbait" than anything.
My suggestion is to start with digital data and logic circuits; how everything a computer does is based on a huge number of switches making very simple decisions.
The approach taken by Charles Petzold in his book "Code" is definitely accessible, though kids don't really need Morse code and flashlights any more when they all have iphones...
My suggestion is to start with digital data and logic circuits; how everything a computer does is based on a huge number of switches making very simple decisions.