Why should community service for students be considered mandatory or not?

Community service helps a persons community in many ways. From helping at food banks to being a volunteer in a clothing drive. If it was a mandatory activity the entire concept of citizens helping others would be damaged. Most community service projects will be enhanced when it's being done for the sole purpose of helping. If it was mandatory, that enhancement is lost. It's better for a court of law to use community service as part of a sentence. It's a mild one and suitable for minor offenses.