One essential - existential - skill that children learn is to please ADULTS (Authoritarian Domineering Unseeing Ludicrous Tedious Superhypocritals). Their actual survival (food, shelter, safety), their welfare, their happiness depends extremely on Adults. If you were in their shoes in regard to some authority - especially an authority that behaves as badly as Adults - you would learn too.
They learn how to not upset Adults (and how to effectively upset them too), how to be pleasing, how to stay out of trouble, how to utterly lie and not get caught. Teens are advanced children in this respect.
Now you might think you are too smart to be fooled, and that of course is your downfall (didn't you read in school about hubris and arrogance?). The kids are humans, it is very high stakes for them and they study and hone every technique. For them it is their most productive skill. You are massivly outgunned. Adult.
You might think you are good-willed and trustworthy, but you are inescapably an Adult. You have that unchecked power and have been corrupted by it. Even if you are truly a friend now you can switch on that power in a moment if something bothers you, at your whim, by your mood. It's like petting an unrestrained lion; no matter how calm and playful it seems, licking you, nuzzling you, purring ... you are paying very close attention and tailoring every move to its pleasure. What if something scares it?
I work to maintain great empathy for children's position (hard to do, because I am corrupted by unchecked power). When interacting, I keep my mouth shut - a whispered syllable dominates the conversation, even if to provoke resistance. I listen attentively: are they speaking with their own voice, for their own cause, of their own perspective? A good signal is if it's too pleasing, if it fits so beautifully and joyfully in my beliefs, relieving all tension - here is a child who understands! Lol. Other people, especially with the vastly different experience of a different generation and of childhood, will have very different ideas and perspectives, many hard to understand or uncomfortable. Just think what you sound like to them.
When kids do that pleasing thing, what response do you see? You see Adults compliment them - 'what fine children!' The Adults are suckers, and if you think back to your teenage years, you know it. Adults are so easy.
There's another issue here. I was once at a casual Adult dinner party and a couple had brought their only child, a 13 year old. The child, as far as I could tell, was the Adults' best friend and they said as much. I tried engaging the child away from their parents and give them some space to be themselves, to be valued as themselves. They said they wanted to be there, with Adults (lol), because 'who wants to hang out with 13 year olds?' So truly heartbreaking.