College courses aren't standardized, but calculus is often a weeder class and far more difficult than previous classes. This is often unintentional. The real p

College courses aren't standardized, but calculus is often a weeder class and far more difficult than previous classes. This is often unintentional. The real problems are that kids are being passed through high school without learning math and that the other college classes are far too easy and lack any rigor. Therefore a class that requires memorization/understanding of concepts and isn't open book is considered incredibly difficult. If english/history/science general education classes weren't such jokes then calculus wouldn't be considered a bottleneck.