In the old days, a guidance counselor would work mostly in high schools, helping students set up their class schedules and decide what they’ll do after graduation. But today’s school counselors have broader responsibilities, including being trained to recognize mental health issues in students before a crisis occurs. The counselors play an integral role, but they’re in short supply and woefully unrepresented in schools, state data show, even as violence has shattered the notion that schools are safe and students remain stigmatized by mental health problems.