Children's groups, like the Boys Scouts and the Brownies, are always looking
for projects that will help needy people. Make a list of the food and gifts
which young children and teens can make or collect to help the homeless. Then
take that list to the teacher or group leader and discuss which ones would be
appropriate for that age group and community. How about offering your services
to help the children carry it through?
This is a great way to involve kids and to teach them about the needs of the
homeless.
Here's a list of some of the groups you might approach:
54 Ways You Can Help
The Homeless - Overview 
Real People 
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