In the UK to be expelled the student/pupil would have had to have committed some serious criminal offence. But some schools might expel for drug addiction or similar. I personally think that often expelling causes more problems, because then the expelled student becomes a member of an exclusive group and they can begin to take a false pride in being a member of that group that leads to the start of the problems Chris mentioned. What is needed is discipline and schools that care more for an individual student than fulfilling the political correct government administrators ranking in the schools league.

У нас, если ребёнок не успевает за остальными, то его просто переводят в школу для умственно отсталых. А в капитализме есть как гувернёры для элиты (см Бэтмэн), так и "пшол вон на улицу" (см Миллионер из трущоб). Кстати, для детей инвалидов даже у нас есть "учителя надомники". Непонятно, что Вас так удивило -- такое впечатление, что в погребе держат и на улицу не выпускают.

In the United States, schools will typically warn a student if they are at risk of being expelled. If a student does something worthy of being expelled over, they will likely get suspended for a while, and the school will tell the student that they'll be expelled if they do it or anything like it again.

of course it doesn’t mean your life is over (...?) you either transfer to a new school or get education online. both options available in ukraine in most cases families whose kids get to the point of dropping out don’t really care about their education anyway so kids either get jobs or just hang out on the streets

Often in the US kids are expelled for extreme inappropriate behavior resulting in expulsion from that school. After that the kid must find another school to attend or they can enroll in online studies.