Would be really cool if public schools provided a free domain and basic hosting for any interested middle/high school student.
But sure, yeah, there'd be some admin time spent managing it. As with anything, there are plenty of reasons not to do it. It struck me as a low cost-to-impact ratio thing that could get kids into tech, but reasonable minds could disagree.
It would result in rampant wildness and people complaining, but if you didn't do it that way the burden would be too high.
(1 teacher / 20 students) * ($50k / teacher-yr) = $2500 per student per year to fund teacher salary.
Compare that to $40/yr domain+hosting, which maybe 10% of students will use. $4/student-yr will not be the diffence between paying teachers probably or not.