The other infantilising thing about UK schools are the school uniforms. I know they're not unique to the UK, but it's one thing that's well-known. Almost all primary and secondary schools make children wear them, with only a few exceptions. I was at primary school in an odd period when primary school children didn't have to wear uniform, it was a bit of a shock when I went to secondary school. The strictness of this varies: usually, the more posh the school, the more strict the uniform policy is. Children can be "isolated" for uniform breaches, or sent home. It used to be common practice for school girls to be made to kneel, to check their skirts were long enough to touch the floor. When a new head teacher takes over a school, sometimes one of the first things they do is to change the uniform to "make their mark", or to really toughen up existing rules. "Things are going to be different now I'm in charge."
Uniforms are sold as an "equaliser", making it harder to tell the rich and poor kids apart, although in practice, it does no such thing. There are also non-uniform days, usually about once each term. It's also notable that children often look much older when they're out of uniform. Also the difference between what boys and girls wear: girls' uniforms are often less practical: they wear T-bar shoes that make their feet wet, and some schools tell them not to do handstands in the playground because of their dresses.
I don't think there's anything inherently bad about being told to "think about going to the toilet". I learned this the hard way as a young adult, when I did a job involving being in a car a lot of the time in a big city, and public toilets are as rare as hens' teeth in rough areas. I worked out that I needed to go at least once every three hours in the day, and I had to plan rest stops into my day. Before that, I had been used to there always being a toilet nearby, and I had never really had to think about how often I went.
