Fences are fine. Especially for young kids near the playground and streets.

Except the fact you need to maintain it (which will be in the form of a replacement every 73 years when enough kids get stabbed by it) and it needs to have enough exit points in case of emergency. It shouldn’t funnel everyone to one spot in the front.

My immediate answer was yeah why not, but then I read the comments about prison fences and realised I was missing some American specific context. The fence’s at my schools were waist high with open gates. They were more of a boundary marker than anything else.