community service

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Services volunteered by individuals or an organization to benefit a community or its institutions.
• noun Similar work performed by law offenders to serve a sentence in lieu of or in addition to jail time.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Service or activity done for the benefit of the community at large, such as cleaning, fundraising, pro bono professional services, etc.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a service that is performed for the benefit of the public or its institutions
• noun an unpaid service for the benefit of the public that is performed by lawbreakers as part (or all) of their sentence