My kids are too old now, but their old school (age 3 preschool-9th grade) passed out the UNICEF boxes every year. One of the classes was responsible for it and sometimes there would be a class party or something if one class brought in an impressive amount.

My kids hated going around and asking for money though, so they often left the boxes at home and we'd trade them some of the candy they got for money for their boxes (a GREAT way to make sure they don't overindulge)