A fixed wheel counts as a brake, though I've only seen the law in relation to bicycles which require 2 working brakes not sure how this applied to unicycles.
The increasing prevalence of non-standard evaluation in R packages was one of the major reasons I switched from R to python for my work. The amount of ceremony and constant API changes just to have something as an argument in a function drove me mad.
If you've ever had to deal with the UK police as a victim of a crime, you'll quickly find out they're pretty useless at obtaining CCTV footage. I was asked to get it myself, to which the business who owned the CCTV told me they would only hand it to the police, so nothing happened.
I'm not sure which European country you're thinking about, but we had lockers, individual backpacks and heavy textbooks. I never used my locker because we didn't have enough time between lessons, so I just carried all my heavy textbooks for the day as did most people.