I went to a secondary school in Wales and on stuff like sports day etc we were put into 'houses' which were named after famous mines in Wales. They were only used from Year 7 till Year 10. If someone in our house did well on say sports day, we would get points. At the end of the days, or terms a 'house' would get a prize (usually its sweets, or sometimes you could have a cinema gift card/wh smith giftcard)It’s not uncommon, it depends on the type of school. In most cases, you’ll have a number of ‘houses’ - usually named after famous people, places or things - and pupils join a house when they join a school. Normally people just get divided up fairly randomly to keep the houses even and it’s meant to encourage a sense of community. You’ll earn points for sporting achievements or doing well in a class, and there might even be inter-house competitions for things like sports and music. At some independent boarding schools then your house might actually be the physical place where you live, more like Harry Potter. There houses can be split by year groups or multi-age.
I don't really think they do them anymore in my old secondary school though, as I asked my younger brother and he had no clue what i was talking about.