Former Boston Celtics guard Chris Herren will speak Thursday at Westwood High School on making decisions to choose alcohol or drugs over school and career. Herron’s appearance is made possible by seven students in the school’s Education Cooperative who have been raising funds all year. Teacher Katie Wood praised her students, many of whom live with multiple challenges, including autism. “We are hoping [his] speech will have a positive effect on the students in the attempt to prevent substance abuse among teens.” Herren has been alcohol and drug-free since August 2008. In June 2009, he launched Hoop Dreams with Chris Herren, a basketball player development company to mentor players on and off the court.