A "Saturday Night Live" skit about a male student having sex with his female high school teacher painted the relationship as every teen boy's dream, but drew a firestorm of criticism on social media. The reaction to the comedy sketch reflected a growing view among law enforcement and victims' advocacy groups that it is no laughing matter when a woman educator preys on her male students. In U.S. schools last year, almost 800 school employees were prosecuted for sexual assault, nearly a third of them women. The proportion of women facing charges seems to be higher than in years past,...