Here are some channels I like:
https://www.youtube.com/c/Techmoan
https://www.youtube.com/channel/UCtM5z2gkrGRuWd0JQMx76qA
The latter channel is perhaps not great for children because of his somewhat relaxed attitude toward mains voltage, but it's great for me.
PhotonicInduction is the extreme version of this, he's an electrical engineer / "mad scientist" who builds ridiculous things such as enormous capacitor banks for blowing things up, power supplies that deliver many kV for feeding to various household appliances, record players that spin at 10,000 RPM and that kind of thing. He also demos old tech you wouldn't see in other places like mercury arc rectifiers. Definitely "don't try this at home" but it's usually really interesting to watch.
For those ever so slightly more lazy than me and beyond :P
https://www.youtube.com/c/K%C3%AAnhs%C3%A1ngt%E1%BA%A1oVN-tr...
Just type "Lifehack" into youtube and search. Extremely low signal to noise ratio in videos made with monetization above all else. It's quite tragic.
A counterexample would be colinfurze[0] who makes very entertaining and inspiring videos. Apart from being a two legged OSHA violation his content is top notch. [0]: https://www.youtube.com/user/colinfurze