Prejudice - (preconceived opinions not based on reason or actual experience) students with better SAT scores will perform better in college. There’s no evidence to support this and it is still a major deciding factor in college admissions.
Discrimination - (unjust treatment of different categories of people) the argument over what is “just” treatment will likely never end. I believe it is unjust that primary school districts in the USA can vary wildly in quality.