Not to rain on this parade but do you know how many grains of rice it takes to make a pound? Over 29,000 (www.riceassociation.org.uk/factsandfigures.htm) so while 3,000 grains may seem like a lot you would have to do 3,000 grains a day for ~10 days to donate a pound of rice.
Thats not to say you should stop, just raising awareness.
I discovered this site when it first opened, it's a great cause and you can take part in it in such a convenient way. When you're bored, you can easily put food on the plates of people in dire need of it.