From left, Dr. William Hauda, an emergency room physician at INOVA Fairfax Hospital, Capt. Bruce Ferguson, commander of the Fairfax County Police Department’s Youth Services Division, Ryan Smith, a graduate student at Virginia Tech, Casey Lingan of the Commonwealth’s Attorney’s office and Mary Ann Sprouse, director of Alcohol, Drug and Health Education at George Mason University address parents and students at Herndon High School Tuesday, April 24.