Bring the pledges with you to the office and ask your co-workers to donate ...
From January this year, I have met this kind of things quite a few times, my co-wokers just put the pledges in the reception and sent an email...It really works.
You can ask your kid to knock the door to sell the 巧克力...it's good for her/him...
We moved to a new neighbourhood a few months ago...we bought 巧克力 from all the kids knocking our door We usually ask the kids, tell me which one you think is the best, then I'll buy it..., the kids always answer our questions very seriously