They should be treated as high school students. And what that means is yes some are approaching adult and need treated as such and others are still operating like children and need treated as such. It isn't a one approach fits all.

My wife teaches English and Special Education in high school and participates in writing a lot of IEPs. Clearly some teens are ready for more adult-like treatment. Others may only make it out of high school with very careful guidance through whatever ends up being their IEP. And in some more rare cases, they may never mature enough or learn enough to even complete high school. So considering those latter examples, it would be foolhardy to conclude we should just treat all high schoolers like they're about to take the world by storm. Because not all of them are. Let's not sell everyone short by treating them all like children. And let's not give them all autonomy like they're college prep superstars. The population is a blend, the approach needs to be a blend.

Most people remain children all their lives. Some teachers act like children too. Therefore, the concern is not just limited to school children. Should some adults be treated like children? Yes!

Some adults should be treated like children, and some children should be treated like adults. I speak for myself when I say I now some high (and middle!) school students that are more mature than many people at the head of this country and others. Taking my own age into account, I would say that it really depends on whether they deserve to or not, but generalizations shouldn't be made based on age; not all middle/high school students should be treated like children.