School administrators sometimes implement the stupidest policies based on correlations of various strengths. But even a strong correlation might have nothing to do with causation.
E.g.: A school my wife used to work at is requiring all 8th graders to take algebra (normally a high-school-level class in the US) regardless of math aptitude because some study shows that 8th graders who take algebra have improved outcomes. Nevermind the fact that this is almost certainly because kids who are already good at math will both take algebra AND have improved outcomes.
E.g.: A school my wife used to work at is requiring all 8th graders to take algebra (normally a high-school-level class in the US) regardless of math aptitude because some study shows that 8th graders who take algebra have improved outcomes. Nevermind the fact that this is almost certainly because kids who are already good at math will both take algebra AND have improved outcomes.