> My kids however are leisurely creatures
How so? They are forced every weekday under duress of the law to go to a place they didn't choose to be. If they don't perform in their forced labor they are put into more forced labor. They have to listen to you and you probably very often take away their agency to do what they desire. Kids do have more "free" time, but that time is not actually free. But the way the can spend is very narrow. But more time does not equal better.
You grew up middle or upper class and the person you’re responding to didn’t, or had no or very bad relations with their family such that they didn’t or couldn’t help.
Don’t forget that school is the most orderly environment lots of children experience, the one where they’re most likely to be around educated people, intellectual stimulation, the least violent, the one where they’re reliably fed. Without the pretense that it’s about education that would be hard to keep up.