Or gaming systems to get bonus points for difficulty - typical example is a kid with maths talent doing double math physics chemistry and taking uni maths as an extra; the uni maths even gave us a heads up on what the upcoming assessment tasks for the other maths would be (we just had 2 hours to solve not 2 weeks); use the maths for a lot of the physics as well, So only really end up studying maths, a little physics and the chemistry. And get rewarded for "difficulty" compared to the humanities student who does english, single math, history, geography, a language and drama - 6 separate subjects with no overlap - and get penalised for "easy subjects"