No, but if we're forcing the kids to have clear backpacks because of an infinitesimal risk, we should ban them from biking to school, being driven to school and playing in the school football team.
Some schools actually have banned things such as biking to school, along with playing tag, balls, and even running during recess over the same safety boogieman. It's frustrating how the whole freedom vs security balance thing falls off a cliff when children's rights are discussed.
As a child, it is exactly prison, it's not 'like' prison. You are controlled in location, action, and speech. You are told when to use the restroom, when to eat. Feeling sleepy today or maybe not getting along with an obnoxious inmate? Too bad for you, you're powerless.
I personally believe most school violence is induced by the prison-like nature of schools. They are inmate riots of 1.
That's a poor comparison though. Both of the others provide other benefits: a method of commuting to school or exercise. Potentially even scholarships.
Imagine you're a teenage girl and you need to carry sanitary products with you. I imagine that for some of them this is essentially a nightmare scenario. That's a direct harm to kids.
Sources edit:
https://www.bicycling.com/news/a20026414/why-biking-to-schoo...
https://www.telegraph.co.uk/news/2016/10/03/parents-outrage-...
https://www.thehealthjournals.com/youre-not-it/amp/