I completely messed up a French test on purpose, so the teacher had an excuse to put me in the class below. We really didn't like each other, and I did much better being in the top 25% of the middle class, rather than the bottom 25% of the top class.
British teachers call splitting up a year by ability for all subjects "streaming", and just for some classes "setting", and searching with both terms shows there's plenty of debate on the merits of each (or neither) method at all ages. Since I left the UK, it looks like politicians have been trying to get involved.
Ended up failing the elementary school test and was 1 out of 4 in the district who aced the middle school placement test to skip prealgebra (math 6 to algebra directly). Much of this can't be done nowadays because of common core.
By the time I went through precalc and calc at MV I realized maybe I should've taken a slower math sequence XD
Tons of privilege-this and that (this is normal in the bay area, pretty sure a lot more schools have similar systems) but at the end of the day kids (like me) studied extremely hard for these placement tests.