As test prep for the SHSAT exam has become more widespread, diversity has plummeted. Schools like Stuyvesant have wound up in highly public cheating scandals. Without greater student-body diversity, schools like Stuyvesant may never be able to curb cheating because it becomes too commonplace; students will continue to do it until they get caught. Students who have taken test prep who may not otherwise meet the criteria for admissions to these elite schools may feel pressure to succeed at all costs.
http://www.nydailynews.com/opinion/ny-oped-diversify-elite-schools-for-all-20180716-story.html