To volunteer means to offer your time and effort to help others or contribute to a cause without expecting payment. Drew requires students to volunteer for 100 hours during high school, it's probably to encourage community involvement, build character, and help students develop important skills like teamwork, leadership, and responsibility. Volunteering can also look great on college applications and job resumes, as it shows commitment and a willingness to contribute to society.
On MLK Day, a group of Drew students and I helped feed the homeless for my friend's nonprofit organization.